2 . The little boy stared at the strange man questioningly, not ________ (know) whether to believe what he had said. （所给词的适当形式填空）

3 . _____________________ metals are very important in our life.
众所周知，金属在我们的生活中很重要。

5 . As I don’t know her address, I had better telephone her to come over. (句型转换)
→________, I had better telephone her to come over.

6 . ________ that you’re going to Beijing , I’m more than pleased to give you some advice.
知道你要去北京, 我非常高兴给你提一些建议。

7 . 知道很多人欣赏我所做的事情真让我开心。(appreciate)(汉译英)

8 . 不止一个学生知道你的秘密。
______ ______one student ______ about your secret.

9 . 又累又饿，一个汉字也不认识，我们压根儿不知道如何点餐。
____________, hungry, and _____________ ____________ a word of Chinese, we had no idea how to order, so the chef just began filling our table with the best food we had ever eaten.