keep ??

　　［误］ She was keeping something to her father.??

　　［正］ She was keeping something from her father.??

　　［析］ "对某人隐瞒某事"要用"keep something from somebody"句型。??

　　［误］ He kept to repeat the word again and again.??

　　［正］ He kept repeating the word again and again.??

　　［析］ keep doing something为连续不断地做某事。有时可以与keep on doing something互换。它们的区别在于keep doing something意为该动作一直不停地在进行中，如： When the train started, she kept waving her hand. 而keep on doing something则表示该动作可能停停顿顿但却一直在进行中，如： He kept on making the same mistakes in grammar.

　　［误］ We must keep up the times.??

　　［正］ We must keep up with the times.??

　　［析］ 这句话意为"我们必须赶上时代"，keep up with是"赶上"之意，而keep up则是"坚持下去"的意思，如： Keep it up, don't stop now!??

　　key ??

　　［误］ I lost the key of the door.??

　　［正］ I lost the key to the door.??

　　［析］ 英语中讲某某的东西一般要用of，而key, entrance, answer则多用to，如："门的钥匙"为key to the door, "高速公路入口"为entrance to the highway, "问题的答案"为the answer (key) to the question.??

　　kind ??

　　［误］ This kind of books are not good.??

　　［正］ This kind of books is not good.??

　　［析］ kind在这种句式中应作为主语，如果讲Those kinds of books are very good. 则是正确的。??

　　kind sort type ??

　　kind和sort为同义词，意为"种类"，而type则为"型号"，如： What type of this car do you want?(你想要这种车的什么型号?)??

　　knock ??

　　［误］ Someone was knocking the door.??

　　［正］ Someone was knocking at the door.??

　　［析］ knock虽可以作及物动词，如： The car knocked a hole in the fence. 但作"敲门"讲一定要用作不及物动词： knock at (on) the door.??

　　know ??

　　［误］ I want to know to play this game.??

　　［正］ I want to know how to play this game.??

　　［析］ 要注意英语中在不定式前加疑问代词或疑问副词的用法。如：I want to know how to do it / what to do / when to do it / where to go.??

　　know know of ??

　　I know him.为"我很了解他。"而I know of him. 则为"我听说过他。"同样的用法还有hear和hear of这一词组。??