根据句意，用所给词的适当形式填空。
I don't understand what they are saying because they speak too ________(quick)．
－Do you have a pen pal, Jeff?
－Yes．He's an ________(America)boy．
The famous ________(sing)is going to give a concert to raise money for charity．
根据下面句子的意思，用括号中所给词的正确形式填空，每空限填一词。
Computers are ________(wide)used in our daily life．
Before making an important ________(decide), think it over．
It’s hard to give up ________(smoke), but you have to．
Jim is fond of sports now, so he is much ________(healthy)than before．
He is going to celebrate his ________(forty)birthday this Saturday．
用括号内所给动词的适当形式填空。
He said that he ________(come)back in five minutes．
He kept on ________(talk)until the class was over．