Opposites with un-, ir-, il-, im-
A prefix goes at the beginning of a word and changes its meaning. Four small word starters, un-, ir-, il- and im-, each turn a word into its opposite. We use un- before most words: usual, unusual; well, unwell. We use ir- before words that start with r: responsible, irresponsible. We use il- before words that start with l: legal, illegal. We use im- before words that start with m or p: possible, impossible; patient, impatient. Read the table.
| Prefix | Used before | Examples |
|---|---|---|
| un- | most words | unwell, unusual, unhappy |
| ir- | r | irregular, irresponsible |
| il- | l | illegal, illogical |
| im- | m or p | impossible, impatient |
What is the opposite of possible?
Impossible. We use im- before p.
And the opposite of legal?
Illegal. We use il- before l.
Last week Omar was unwell. He wanted to play football, but it was impossible because he had a cold. He was impatient and a little unhappy. His mother said: Be patient. It is irresponsible to play when you are ill. After three days, Omar felt better. He went back to school and played football again.
Opposite cards. Write ten words on cards: well, possible, legal, patient, responsible, usual, happy, polite, regular, lucky. The child adds the right prefix on a second card: unwell, impossible, illegal, impatient, irresponsible, unusual, unhappy, impolite, irregular, unlucky. The grown-up checks the spelling.