A prefix is a group of letters placed at the start of a root word to change its meaning. Some complicated words are less difficult to spell if you are familiar with prefixes.

Here are some common examples in the following list:

PREFIX	MEANING	EXAMPLES
anti-	against or opposite to	anticlockwise, antibiotic
auto-	self	autobiography, automat
dis-	not, or away	dissimilar, disconnect
in-	not	insane, inhuman
il-	not	illogical, illegal
im-	not	immature, improbable
ir-	not	irrelevant, irregular
inter-	between	international, intermarry
mis-	wrong	misunderstand, misspell
post-	after	postnatal, postscript
pre-	before	prenatal, prehistoric
pro-	for, or forward	propose, pro-British
re-	again, or back	rewrite, reconsider
sub-	under	submarine, substandard
super-	above	supervisor, superhuman
trans-	across	transport, transplant
un-	not, or in reverse	unfinished, unarmed

 

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