1. 那时他正在努力算这道数学题。 He was trying hard to

问题：

1. 那时他正在努力算这道数学题。   

     He was trying hard to                   this math problem at that time. 

2. 史密斯先生说话很慢以便学生们能够听清楚。

     Mr. Smith speaks slowly                   the students can hear him clearly.   

3. 今天天气很好，为什么不去散步？

    It's fine today._         ____go out for a walk? 

4. 你最好不要过分依赖父母，要学会照顾自己。   

   You'd better not        too much        your parents, and learn to look after yourself.    

5. 对不起，刚才我错拿了你的伞。

   Sorry, I  took your umbrella                  just now.

6. 昨天你发生了什么事？  

   What        you yesterday?

7. 乘电梯到二楼，向右拐。  

            the elevator         the second floor and turn right.