1.The computer doesn't work well,so something___wrong.a.can have goneb.should have gonec.must have goned.ought to have gone2.I'm going to America for a holiday next week.____.a.with pleasureb.with you successc.for sured.that's great3.The government official explained that there's no point___about the cultural gap in that city.a.to worryb.with them worryingc.in worryingd.worry4.Many Americans worry about leisure and hurry from one activity to the next,

C
情态动词表示猜测
对过去的猜测
must have done 肯定
may have done 可能
cant have done 不可能
对现在的猜测
must be 肯定
may be 可能
cant be 不可能
2.D
那太好了，这个就是一般的生活用语
3.A point to do 指出……
*官员……没有必要……
4.B
因为前面句子已经完整，后面如果主语相同，那么可以省略连词，主语和助动词，ing 表示主动，ed表示被动
5.A
claime 声称
demand 要求
argue 争论
announce 通知
放心，我解释的应该都对的

.The computer doesn't work well,so something__C_wrong.
a.can have gone
b.should have gone
c.must have gone
d.ought to have gone
2.I'm going to America for a holiday next week._D___.
a.with pleasure
b.with you success
c.for sure
d.that's great
3.The government official explained that there's no point_A__about the cultural gap in that city.
a.to worry
b.with them worrying
c.in worrying
d.worry
4.Many Americans worry about leisure and hurry from one activity to the next,__B__little time to stop and think.
a.leave
b.leaving
c.left
d.to leave
5.He_A_that he could create live fish out of chemicals.
a.claimed
b.demanded
c.argued
d.announced