10th grade Advanced. Unit 7. Lesson 4. Greatness

👉Communicative area: reading and speaking about great people in history

👉Active vocabulary: society, nurture; negative affixes – anti-, dis-, il-, im-, in-, ir-, un-; unsociable, immoral, dishonest, immortal, unbelievable, impossible

These common prefixes—anti-, dis-, il-, im-, in-, ir-, un-—are added to the beginning of words to create antonyms or negative meanings. They generally mean "not" or "opposite of," with specific usage rules based on spelling or word origin (e.g., il- for 'l', ir- for 'r', im- for 'p/m'). 

Detailed Usage of Negative Prefixes:

• Un- (not/opposite): The most common, used with many adjectives and verbs (e.g., unhappy, unusual, unlock).
• Dis- (not/opposite/reverse): Often used with verbs, adjectives, and nouns to show reversal (e.g., disagree, dishonest, disappear).
• In- (not/opposite): Used with many consonants and vowels; often changes form based on the root word.
  • In- + c, active, etc.: Incorrect, inactive, incapable.
• Im- (not/opposite): Used primarily before words starting with 'm' or 'p' (e.g., impossible, impolite, impatient, immature).
• Il- (not/opposite): Used exclusively before words starting with 'l' (e.g., illegal, illogical, illegible, illiterate).
• Ir- (not/opposite): Used exclusively before words starting with 'r' (e.g., irregular, irresponsible, irreplaceable).
• Anti- (against/opposed to): Indicates opposition or destruction (e.g., antibiotic, antisocial, anti-war). 

Key Distinctions and Examples

• Dis- vs. Un-: Dis- often reverses an action (disconnect), while un- implies a state of being not (unhappy) or removing something (unlock).
• Exceptions: Un- is very flexible, but some words take dis-, in-, or im- exclusively (e.g., disloyal, not unloyal).
• Disinterested vs. Uninterested: Disinterested means neutral or impartial, while uninterested means bored or not caring. 

Summary Table

Prefix	Meaning	Examples
Un-	Not, opposite, removal	Unusual, unhappy, unlock, undone
Dis-	Not, opposite, reverse	Disagree, dishonest, dislike, disconnect
In-	Not, opposite	Inactive, invisible, incapable, informal
Im-	Not, opposite (before p/m)	Impossible, impolite, impatient, immature
Il-	Not, opposite (before l)	Illegal, illogical, illegible, illiterate
Ir-	Not, opposite (before r)	Irregular, irresponsible, irreplaceable
Anti-	Against, opposed to	Antiseptic, antisocial, antifreeze, antibiotic