根据句意，用所给词的适当形式填空。

1．The famous                （sing） is going to give a concert to raise money for charity．

2．--Do you have a pen pal, Jeff?

    --Yes．He's an               （America） boy．

3．I don't understand what they are saying because they speak too             （quick）．

4．I didn't finish               （write） my test because I ran out of time．

5．All of us felt               （excite） and proud when we watched China's first-ever spacewalk at 4:43 pm on September 27, 2008．

根据句意，用所给词的适当形式完成句子：

1．The river _________ （pollute）badly．There are no living things in it．

2．Boys and girls，you must pay attention to the traffic _________（safe）．

3．Edison had many _________（invent）in this life．

4．We study hard in order to get a higher _________（educate）．

5．The teacher enlarged the picture on the screen to make it _________（see）clearly by all the students．