- 知道，了解，懂得，通晓，掌握…的知识(或技能)：
Does he know English?
他懂英语吗?
I know the facts.
我了解事实情况。
He knows how to play chess.
他会下棋。
- 确知，确信，确认：
I know that he's a good man.
我确信他是个好人。
- 认识；相识，结识：
I never know such a man.
我从不认识这样一个人。
He knows my brother.
他认识我弟弟。
I know of him, but I do not know him personally.
我听说过他，但我并不认识他。
- 记得，牢记，熟记，背熟：
I know an old song about love.
我记得一首关于爱情的老歌。
The actor knows his lines by heart.
那位演员能够背诵自己的台词。
- 认出，辨认出：
I knew him for a Frenchman.
我认出他是一名法国人。
I knew him at once.
我立即认出了他。
- 分辨，识别：
You should know right from wrong.
你应当明辨是非。
- 见到过；听到过[一般用于过去时或完成时]：
I've never known him to cry.
我从未见过他哭泣。
I never knew anyone who could walk on his head.
我从未听说过有人能倒立着走路。
- 对…有研究，精通：
He knows literature.
他对文学很有研究。
- 经历，经受，体验：
He has known better days.
他曾过过好日子。
He knew poverty and sorrow.
他经历过穷苦日子。
- 受…支配(或影响)：
His wrath knew no bounds.
他怒不可遏。
- [古语]与…性交，与…发生性关系