know one's ABCs
знать основное о чём-либо, иметь базовые знания
The woman in the library knew her ABC's and could quickly give me the information I needed.
Другие идиомы:
- know where all the bodies are buried
- know one's stuff
- know the score
- know one's place
- not know if one is coming or going
- know what's what
- know a trick or two
- know-it-all
- know (something) from memory
- know one's own mind
- know which side one's bread is buttered on
- know (something) only too well
- know the ropes
- know (something) inside out
- know (someone) by sight