Letters added at the beginning of a root word to change its meaning Prefixes: Letters added at the beginning of a root word to change its meaning
con- with, together Ex. conjoin conjunction connect _______________
de- from, reverse Ex. detach deflate detour ______________
ex- out, former, beyond Ex. exhale ex-husband extraterrestrial _______________
dis- not, opposite of Ex. dislike dishonest disconnect _____________
im- not, opposite of Ex. improper impossible immature _____________
in- not, opposite of Ex. inconsistent incompetent incomplete _____________
un- not, opposite of Ex. unequal unable unzipped _____________
Let’s Practice If certain means “sure,” then uncertain means: beyond sure with sure from sure not sure
The answer is d because the prefix “un” means not. certain = sure uncertain = not sure
Let’s Practice If the prefix con means with or together, what does consensus most likely mean: Your sense of smell is well developed to make a decision with a group having a lot of money studying hard for a test
Answer The answer is b. con = together sensus = latin root meaning to think or understand consensus = making a decision together as a group
Let’s Practice If the word increase means to grow in an upward fashion, then decrease probably means: to grow faster to grow slower to shrink get rid of creases
Answer The answer is c. de=means reverse increase = to grow decrease = to shrink
Let’s continue with more prefixes
sub- under Ex. submerge subway submarine _____________
pre- before Ex. preheat precede prehistoric _____________
cent- a hundred Ex. centipede century centimeter _____________
anti- against Ex. antivirus antifreeze anti-bullying ____________
multi- many Ex. mulitlingual multipurpose multicolored ____________
uni- one Ex. unicorn unidirectional unicycle ____________
mis- wrongly Ex. misunderstood misspelled misbehave ____________
non- not Ex. nonstop nonfiction nonviolent ____________
Let’s Practice What does the word subzero probably mean: below zero a number replacing zero a large 12” sandwich underground
The answer is a. sub = under or below subzero = below zero
Let’s Practice What does the word centiliters probably mean: Not able to litter a liter full of pennies one hundred letters sent together a metric unit of volume equal to one hundredth of a liter
Answer The answer is d. centi = a hundred liter = a metric unit of volume centiliter = A metric unit of volume equal to one hundredth of a liter
In conclusion Prefixes are letters added at the beginning of a root word to change its meaning. Knowing what prefixes mean will help you better understand the meaning of unknown words.
You are now on your way to becoming a prefix expert! Congratulations You are now on your way to becoming a prefix expert!
This Prefix PPT was created by: Cristina de Cardenas 2012