3. How come？ 怎么会？ 怎么回事？表示某件事情很奇怪，有点想不通；可单独使用，也可引导一个问句， 相当于疑问句 why, 但 how come 开头的特殊疑问句使用的仍然是陈述语序。

　　eg:How come Tom didn't come to the party?

　　　 = Why didn't Tom come to the party?

4. (1)stay up late 指"熬夜到很晚，迟睡"。 Don't stay up late next time.

5. (2)stay up 指"熬夜，不睡觉". He stayed up all night to write his story.

6. (1)go to bed 强调"上床睡觉"的动作及过程，但人不一定睡着。

　　　Eg:I went to bed at eleven last night.

(2)go to sleep 强调"入睡，睡着，进入梦乡"。

Eg: She was so tired that she went to sleep soon.

7. find + 宾语 +名词, 发现 ： We have found him (to be) a good

find + 宾语 + 形容词， 发现： He found the room dirty.

find + 宾语 + 现在分词， 发现 ： I found her standing at the door.

8. percent 百分数， 基数词 + percent： percent 没有复数形式，作主语时，根据所修饰的名词来判断谓语的单复数。 Forty percent of the students in our class are girls. Thirty percent of time passed.

9. more than 超过，多于，不仅仅， 相当于 over. 在句型转换中考查两者的同义替换。反义词组为：less than.

Eg: I lived in Shanghai for more than / over ten years.

12. afraid 形容词， 担心的，害怕的，在句中作表语，不用在名词前作定语。