Map physical position and degree with prefixes used in science and everyday words.
9 targets with matrices3 core roots revisited12 mastery checks
THE GIST
The idea behind these word parts
Prefixes can show position or degree. Over- and under- locate things; hyper- can mark an unusually high degree.
Go deeper · how the parts work in context
Hypersensitive combines hyper- with sensitive: responding very strongly or to an unusually small stimulus. This is a difference in degree, not a physical position above something.
hyper + sens + itive → hypersensitive
The sensor was hypersensitive to tiny changes in temperature.
Here hypersensitive means responding to an unusually small stimulus.
Word parts suggest a meaning; the sentence helps confirm it. If the clues are not enough, check a dictionary.
EXPLORE THE WORD PARTS
Meaning, connections, and practice
Choose a word part. Read its gist, explore its map and matrix, then answer its three checks. Open the extra explanation whenever you need it.
How to use a matrix
Leading part + base + ending → word. Choose cells from left to right. Only paths that make one of the listed words are enabled. ∅ means no part is added.
The center can be a root or a whole word. Some cells contain combining forms or grouped endings. Related bases can change spelling, as in scribe/script or mit/miss; follow the spelling notes.
Keep a word for comparison, then select another word to see which parts and meanings changed.
01
over-
above
The gist: overhead means above the head. The clue over- connects it to above.
Why it works · examples & details
The shared clue is the meaning of the leading part: above. Compare overhead (above the head) with overpass (a road passing above another). The complete word’s definition is more specific than the word-part clue.
over + head → overhead Above the head.
The map and matrix show established words. Matching letters alone do not prove a meaningful relationship.
Explore over- · map, matrix & checks
overheadabove the head
overpassa road passing above another
Prefix connections map: over-
Compare this beginning across different bases. These words share a leading part; they do not necessarily share a root. Select a word to load its path in the matrix below.
Read the family first.
over-above
over + head
Above the head.
over + pass
A road passing above another.
over + flightnoun
A flight above an area.
Explain the connection: “These words share ___. In ___ it helps mean ___; in ___ it helps mean ___.”
Build with over- 3 word paths
over-: above. Choose parts from left to right, or choose a word below. Dimmed choices do not continue a word in this matrix.
Prefix / leading part
Root or whole base
Suffix / ending
over + head → overhead
Above the head.
What changed?
Starting word
Selected word
Compare two paths
overhead: Above the head. overflight: A flight above an area.
Say which parts stay and which change. Explain how the meaning or word job changes.
Read every word sum and meaning
Word sum
Word
Meaning
over + head
overhead
Above the head.
over + pass
overpass
A road passing above another.
over + flight
overflight
A flight above an area.
Check your understanding
Use the map and matrix as needed. A wrong answer gives you a clue; try again or open the explanation.
0 of 3 answered correctly
02
under-
below
The gist: underground means below the ground. The clue under- connects it to below.
Why it works · examples & details
The shared clue is the meaning of the leading part: below. Compare underground (below the ground) with underpass (a passage below a road). The complete word’s definition is more specific than the word-part clue.
under + ground → underground Below the ground.
The map and matrix show established words. Matching letters alone do not prove a meaningful relationship.
Explore under- · map, matrix & checks
undergroundbelow the ground
underpassa passage below a road
Prefix connections map: under-
Compare this beginning across different bases. These words share a leading part; they do not necessarily share a root. Select a word to load its path in the matrix below.
Read the family first.
under-below
under + ground
Below the ground.
under + pass
A passage below a road.
under + seaadjective
Below the surface of the sea.
Explain the connection: “These words share ___. In ___ it helps mean ___; in ___ it helps mean ___.”
Build with under- 3 word paths
under-: below. Choose parts from left to right, or choose a word below. Dimmed choices do not continue a word in this matrix.
Prefix / leading part
Root or whole base
Suffix / ending
under + ground → underground
Below the ground.
What changed?
Starting word
Selected word
Compare two paths
underground: Below the ground. undersea: Below the surface of the sea.
Say which parts stay and which change. Explain how the meaning or word job changes.
Read every word sum and meaning
Word sum
Word
Meaning
under + ground
underground
Below the ground.
under + pass
underpass
A passage below a road.
under + sea
undersea
Below the surface of the sea.
Check your understanding
Use the map and matrix as needed. A wrong answer gives you a clue; try again or open the explanation.
0 of 3 answered correctly
03
infra-
below
The gist: infrared means below red on the light spectrum. The clue infra- connects it to below.
Why it works · examples & details
The shared clue is the meaning of the leading part: below. Compare infrared (below red on the light spectrum) with infrasound (sound below human hearing). The complete word’s definition is more specific than the word-part clue.
infra + struct + ure → infrastructure Basic systems, such as roads and railways, that a community uses. It works as a noun in this example.
In a sentence: Railroad infrastructure connected Mexican towns with jobs across the United States border.
The map and matrix show established words. Matching letters alone do not prove a meaningful relationship.
Explore infra- · map, matrix & checks
infraredbelow red on the light spectrum
infrasoundsound below human hearing
Prefix connections map: infra-
Compare this beginning across different bases. These words share a leading part; they do not necessarily share a root. Select a word to load its path in the matrix below.
Read the family first.
infra-below
infra + red
Below red on the light spectrum.
infra + sound
Sound below human hearing.
infra + struct + urenoun
Basic systems, such as roads and railways, that a community uses.
Railroad infrastructure connected Mexican towns with jobs across the United States border.
Explain the connection: “These words share ___. In ___ it helps mean ___; in ___ it helps mean ___.”
Build with infra- 3 word paths
infra-: below. Choose parts from left to right, or choose a word below. Dimmed choices do not continue a word in this matrix.
Prefix / leading part
Root or whole base
Suffix / ending
infra + red → infrared
Below red on the light spectrum.
What changed?
Starting word
Selected word
Compare two paths
infrared: Below red on the light spectrum. infrastructure: Basic systems, such as roads and railways, that a community uses.
Say which parts stay and which change. Explain how the meaning or word job changes.
Read every word sum and meaning
Word sum
Word
Meaning
infra + red
infrared
Below red on the light spectrum.
infra + sound
infrasound
Sound below human hearing.
infra + struct + ure
infrastructure
Basic systems, such as roads and railways, that a community uses.
Check your understanding
Use the map and matrix as needed. A wrong answer gives you a clue; try again or open the explanation.
0 of 3 answered correctly
04
ultra-
beyond
The gist: ultraviolet means beyond violet on the light spectrum. The clue ultra- connects it to beyond.
Why it works · examples & details
The shared clue is the meaning of the leading part: beyond. Compare ultraviolet (beyond violet on the light spectrum) with ultramarathon (a race beyond marathon distance). The complete word’s definition is more specific than the word-part clue.
ultra + violet → ultraviolet Beyond violet on the light spectrum.
The map and matrix show established words. Matching letters alone do not prove a meaningful relationship.
Explore ultra- · map, matrix & checks
ultravioletbeyond violet on the light spectrum
ultramarathona race beyond marathon distance
Prefix connections map: ultra-
Compare this beginning across different bases. These words share a leading part; they do not necessarily share a root. Select a word to load its path in the matrix below.
Read the family first.
ultra-beyond
ultra + violet
Beyond violet on the light spectrum.
ultra + marathon
A race beyond marathon distance.
ultra + son + icadjective
Having a frequency beyond human hearing.
Explain the connection: “These words share ___. In ___ it helps mean ___; in ___ it helps mean ___.”
Build with ultra- 3 word paths
ultra-: beyond. Choose parts from left to right, or choose a word below. Dimmed choices do not continue a word in this matrix.
Prefix / leading part
Root or whole base
Suffix / ending
ultra + violet → ultraviolet
Beyond violet on the light spectrum.
What changed?
Starting word
Selected word
Compare two paths
ultraviolet: Beyond violet on the light spectrum. ultrasonic: Having a frequency beyond human hearing.
Say which parts stay and which change. Explain how the meaning or word job changes.
Read every word sum and meaning
Word sum
Word
Meaning
ultra + violet
ultraviolet
Beyond violet on the light spectrum.
ultra + marathon
ultramarathon
A race beyond marathon distance.
ultra + son + ic
ultrasonic
Having a frequency beyond human hearing.
Check your understanding
Use the map and matrix as needed. A wrong answer gives you a clue; try again or open the explanation.
0 of 3 answered correctly
05
peri-
around
The gist: perimeter means measurement around an area. The clue peri- connects it to around.
Why it works · examples & details
The shared clue is the meaning of the leading part: around. Compare perimeter (measurement around an area) with periscope (a tool for looking around an obstacle). The complete word’s definition is more specific than the word-part clue.
peri + meter → perimeter Measurement around an area.
The map and matrix show established words. Matching letters alone do not prove a meaningful relationship.
Explore peri- · map, matrix & checks
perimetermeasurement around an area
periscopea tool for looking around an obstacle
Prefix connections map: peri-
Compare this beginning across different bases. These words share a leading part; they do not necessarily share a root. Select a word to load its path in the matrix below.
Read the family first.
peri-around
peri + meter
Measurement around an area.
peri + scope
A tool for looking around an obstacle.
peri + card + iumnoun
The sac around the heart.
Explain the connection: “These words share ___. In ___ it helps mean ___; in ___ it helps mean ___.”
Build with peri- 3 word paths
peri-: around. Choose parts from left to right, or choose a word below. Dimmed choices do not continue a word in this matrix.
Prefix / leading part
Root or whole base
Suffix / ending
peri + meter → perimeter
Measurement around an area.
What changed?
Starting word
Selected word
Compare two paths
perimeter: Measurement around an area. pericardium: The sac around the heart.
Say which parts stay and which change. Explain how the meaning or word job changes.
Read every word sum and meaning
Word sum
Word
Meaning
peri + meter
perimeter
Measurement around an area.
peri + scope
periscope
A tool for looking around an obstacle.
peri + card + ium
pericardium
The sac around the heart.
Check your understanding
Use the map and matrix as needed. A wrong answer gives you a clue; try again or open the explanation.
0 of 3 answered correctly
06
super-
above
The gist: superimpose means place one image on top of another. The clue super- connects it to above.
Why it works · examples & details
The shared clue is the meaning of the leading part: above. Compare superimpose (place one image on top of another) with superstructure (the part built above a base). The complete word’s definition is more specific than the word-part clue.
super + impose → superimpose To place one thing over another. It works as a verb in this example.
In a sentence: Allotment helped superimpose an individual property system on collectively held Native land.
The map and matrix show established words. Matching letters alone do not prove a meaningful relationship.
Explore super- · map, matrix & checks
superimposeplace one image on top of another
superstructurethe part built above a base
Prefix connections map: super-
Compare this beginning across different bases. These words share a leading part; they do not necessarily share a root. Select a word to load its path in the matrix below.
Read the family first.
super-above
super + imposeverb
To place one thing over another.
Allotment helped superimpose an individual property system on collectively held Native land.
super + structure
The part built above a base.
super + scriptnoun
Writing placed above the normal line.
Explain the connection: “These words share ___. In ___ it helps mean ___; in ___ it helps mean ___.”
Build with super- 3 word paths
super-: above. Choose parts from left to right, or choose a word below. Dimmed choices do not continue a word in this matrix.
Prefix / leading part
Root or whole base
Suffix / ending
super + impose → superimpose
To place one thing over another.
verb
Allotment helped superimpose an individual property system on collectively held Native land.
What changed?
Starting word
Selected word
Compare two paths
superimpose: To place one thing over another. superscript: Writing placed above the normal line.
Say which parts stay and which change. Explain how the meaning or word job changes.
Read every word sum and meaning
Word sum
Word
Meaning
super + impose
superimpose
To place one thing over another.
super + structure
superstructure
The part built above a base.
super + script
superscript
Writing placed above the normal line.
Check your understanding
Use the map and matrix as needed. A wrong answer gives you a clue; try again or open the explanation.
0 of 3 answered correctly
07
per- (through)
through
The gist: percolate means filter through. The clue per- (through) connects it to through.
Why it works · examples & details
The shared clue is the meaning of the leading part: through. Compare percolate (filter through) with pervade (spread through every part). The complete word’s definition is more specific than the word-part clue.
per + colate → percolate Filter through.
Meaning & spelling: This sense repeats from List 3 with new examples for review.
The map and matrix show established words. Matching letters alone do not prove a meaningful relationship.
Explore per- (through) · map, matrix & checks
percolatefilter through
pervadespread through every part
Prefix connections map: per- (through)
Compare this beginning across different bases. These words share a leading part; they do not necessarily share a root. Select a word to load its path in the matrix below.
Read the family first.
per- (through)through
per + colate
Filter through.
per + vade
Spread through every part.
per + me + ableadjective
Allowing something to pass through.
Explain the connection: “These words share ___. In ___ it helps mean ___; in ___ it helps mean ___.”
Build with per- (through) 3 word paths
per- (through): through. Choose parts from left to right, or choose a word below. Dimmed choices do not continue a word in this matrix.
Prefix / leading part
Root or whole base
Suffix / ending
per + colate → percolate
Filter through.
What changed?
Starting word
Selected word
Compare two paths
percolate: Filter through. permeable: Allowing something to pass through.
Say which parts stay and which change. Explain how the meaning or word job changes.
Read every word sum and meaning
Word sum
Word
Meaning
per + colate
percolate
Filter through.
per + vade
pervade
Spread through every part.
per + me + able
permeable
Allowing something to pass through.
Check your understanding
Use the map and matrix as needed. A wrong answer gives you a clue; try again or open the explanation.
0 of 3 answered correctly
08
circum-
around
The gist: circumference means distance around a circle. The clue circum- connects it to around.
Why it works · examples & details
The shared clue is the meaning of the leading part: around. Compare circumference (distance around a circle) with circumnavigate (travel around). The complete word’s definition is more specific than the word-part clue.
circum + spect → circumspect Careful about possible consequences before acting or judging. It works as a adjective in this example.
In a sentence: A circumspect reader checks who signed the Cherokee treaty before calling it an agreement of the whole nation.
The map and matrix show established words. Matching letters alone do not prove a meaningful relationship.
Explore circum- · map, matrix & checks
circumferencedistance around a circle
circumnavigatetravel around
Prefix connections map: circum-
Compare this beginning across different bases. These words share a leading part; they do not necessarily share a root. Select a word to load its path in the matrix below.
Read the family first.
circum-around
circum + ference
Distance around a circle.
circum + navigate
Travel around.
circum + spectadjective
Careful about possible consequences before acting or judging.
A circumspect reader checks who signed the Cherokee treaty before calling it an agreement of the whole nation.
Explain the connection: “These words share ___. In ___ it helps mean ___; in ___ it helps mean ___.”
Build with circum- 3 word paths
circum-: around. Choose parts from left to right, or choose a word below. Dimmed choices do not continue a word in this matrix.
Prefix / leading part
Root or whole base
Suffix / ending
circum + ference → circumference
Distance around a circle.
What changed?
Starting word
Selected word
Compare two paths
circumference: Distance around a circle. circumspect: Careful about possible consequences before acting or judging.
Say which parts stay and which change. Explain how the meaning or word job changes.
Read every word sum and meaning
Word sum
Word
Meaning
circum + ference
circumference
Distance around a circle.
circum + navigate
circumnavigate
Travel around.
circum + spect
circumspect
Careful about possible consequences before acting or judging.
Check your understanding
Use the map and matrix as needed. A wrong answer gives you a clue; try again or open the explanation.
0 of 3 answered correctly
09
hyper-
over or excessive
The gist: hyperactive means excessively active. The clue hyper- connects it to over or excessive.
Why it works · examples & details
The shared clue is the meaning of the leading part: over or excessive. Compare hyperactive (excessively active) with hypersensitive (overly sensitive). The complete word’s definition is more specific than the word-part clue.
hyper + active → hyperactive Excessively active.
The map and matrix show established words. Matching letters alone do not prove a meaningful relationship.
Explore hyper- · map, matrix & checks
hyperactiveexcessively active
hypersensitiveoverly sensitive
Prefix connections map: hyper-
Compare this beginning across different bases. These words share a leading part; they do not necessarily share a root. Select a word to load its path in the matrix below.
Read the family first.
hyper-over or excessive
hyper + active
Excessively active.
hyper + sensitive
Overly sensitive.
hyper + act + ive + itynoun
An unusually high level of activity.
Drop the final silent e before the vowel suffix: hyperactive + ity → hyperactivity.
Explain the connection: “These words share ___. In ___ it helps mean ___; in ___ it helps mean ___.”
Build with hyper- 3 word paths
hyper-: over or excessive. Choose parts from left to right, or choose a word below. Dimmed choices do not continue a word in this matrix.
Prefix / leading part
Root or whole base
Suffix / ending
hyper + active → hyperactive
Excessively active.
What changed?
Starting word
Selected word
Compare two paths
hyperactive: Excessively active. hyperactivity: An unusually high level of activity.
Say which parts stay and which change. Explain how the meaning or word job changes.
Read every word sum and meaning
Word sum
Word
Meaning
hyper + active
hyperactive
Excessively active.
hyper + sensitive
hypersensitive
Overly sensitive.
hyper + act + ive + ity
hyperactivity
An unusually high level of activity.
Check your understanding
Use the map and matrix as needed. A wrong answer gives you a clue; try again or open the explanation.
0 of 3 answered correctly
DECODE · FOLLOW THE CLUES
Use the clue without overtrusting it
A word part gives you a strong clue—not always a complete definition.
Spot the part.Underline the exact letters you recognize.
Recall the clue.Say the meaning you learned for that part.
Test the whole word.Combine the clue with the other parts and the sentence.
Decode overpass
Spot overpass. The leading word part over- carries the clue above. Here, it helps you understand: a road passing above another.
Decode underpass
Spot underpass. The leading word part under- carries the clue below. Here, it helps you understand: a passage below a road.
Decode infrasound
Spot infrasound. The leading word part infra- carries the clue below. Here, it helps you understand: sound below human hearing.
Compare the meanings, then test which form fits the sentence.
overpass
a crossing above another route
underpass
a crossing below another route
Explain the difference
The base pass stays. Over- and under- change the position.
A common mistake—and how to avoid it
Above can describe position or degree. Hyperactive means unusually active; it does not describe physical height. Check what kind of comparison the sentence makes.
REVIEW · BRING ROOTS BACK
Keep these roots working
Before opening each matrix, recall the root’s meaning. Build the review words, then explain the whole word. These core roots return in later lessons with new word forms.
Some review words use today’s affixes; others bring back an earlier pattern. Not every affix can attach to every root.
spect: look or see. Choose parts from left to right, or choose a word below. Dimmed choices do not continue a word in this matrix.
Prefix / leading part
Root or whole base
Suffix / ending
circum + spect → circumspect
Careful about possible consequences before acting or judging.
adjective
A circumspect reader checks who signed the Cherokee treaty before calling it an agreement of the whole nation.
What changed?
Starting word
Selected word
Compare two paths
circumspect: Careful about possible consequences before acting or judging. inspector: A person whose job is to examine conditions or enforce standards.
Say which parts stay and which change. Explain how the meaning or word job changes.
Read every word sum and meaning
Word sum
Word
Meaning
circum + spect
circumspect
Careful about possible consequences before acting or judging.
in + spect
inspect
To look closely at something in order to examine it.
in + spect + ion
inspection
A close examination.
in + spect + or
inspector
A person whose job is to examine conditions or enforce standards.
cred: believe or trust. Choose parts from left to right, or choose a word below. Dimmed choices do not continue a word in this matrix.
Prefix / leading part
Root or whole base
Suffix / ending
in + cred + ible → incredible
Very difficult to believe or remarkably surprising.
adjective
The speed of the loss of Native land seems incredible until we examine how allotment worked.
What changed?
Starting word
Selected word
Compare two paths
incredible: Very difficult to believe or remarkably surprising. credible: Supported well enough to deserve belief.
Say which parts stay and which change. Explain how the meaning or word job changes.
Read every word sum and meaning
Word sum
Word
Meaning
in + cred + ible
incredible
Very difficult to believe or remarkably surprising.
cred + it
credit
An arrangement that lets someone borrow money or receive goods before paying.
cred + it + or
creditor
A person or institution to whom money is owed.
cred + ible
credible
Supported well enough to deserve belief.
Use it: Write one sentence about history using a review word. Underline its root, circle its affixes, and explain why that word fits your sentence.
QUICK QUIZ · RECALL & APPLY
Recall the parts. Apply the pattern.
Check every target, then complete three applied questions. If you miss one, revisit its matrix and try again. Finish with the new-word challenge below.
CHECK IN CONTEXT
Make sense of a new word
Use both the word parts and the sentence. Open a hint if you need a starting point.
In the formula, the small number sat below the normal line as a subscript.
Expand your thinking · explain it or use itCheck your sentence
Does the word’s established meaning fit your idea?
Does its form fit the grammar of your sentence?
Can you identify a meaningful part and explain its contribution?
These optional notes are not saved, graded, or submitted.
COME BACK · RETRIEVE IT AGAIN
Remember after a break
Return in two days, then about a week later. Before opening the notes, recall a meaning, rebuild two words, and use one in a new sentence.
Start with over-. What does it mean? Which two words connect to it?
Check after you recall
over-: above. For example: overhead and overpass. Explain how each connects to the meaning.
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