Definition / Explanation
Idioms are fixed or semi-fixed expressions whose meaning is not fully predictable from the individual words. At C2, the challenge is not only understanding idioms but controlling how much they can change grammatically. Some idioms allow changes in tense, person, or aspect, while others lose their naturalness if articles, prepositions, or word order are altered. Native-like control depends on recognising which parts are flexible and which are fixed. This is why idioms are best learned as patterns, not as loose vocabulary items. A correct idiom is both meaningful and structurally natural.
Key Rules
- Treat idioms as chunks, not as freely changeable combinations.
- Some variation is possible in tense, person, and aspect: He is pulling my leg, They were pulling my leg.
- Many idioms do not allow article changes, word swaps, or preposition changes.
- Check whether the idiom sounds appropriate for the register and situation.
- If you are unsure, use a clearer non-idiomatic alternative rather than force an unnatural idiom.
Examples
- He has been pulling my leg.
- Do not jump to conclusions.
- We are in the same boat.
- She finally let the cat out of the bag.
- They tried to save face after the mistake.
Common Mistakes
- ❌ We are in same boat. -> ✅ We are in the same boat.
- ❌ Do not jump to conclusion. -> ✅ Do not jump to conclusions.
- ❌ He pulled my legs. -> ✅ He was pulling my leg. / ✅ He pulled my leg.