not know one's own strength
не рассчитать собственные силы
George does not know his own strength, and he is sometimes dangerous to play with.
Другие идиомы:
- not enough room to swing a cat
- neither fish nor fowl
- night owl
- no spring chicken
- not breathe a word (about someone or something)
- not have the stomach for (something)
- not move a muscle
- neck and neck
- new blood
- No sweat!
- number cruncher
- not playing with a full deck
- not bat an eye/eyelid
- naked eye
- not a dry eye in the house