1. Some of the swamps have become polluted.
[考例] The life we were used to ______ greatly since 1992.
A. change B. has changed
C. changing D. have changed
[解析] B。由since 1992可知,本题考查现在完成时。the life作主语,谓语动词的助动词要用单数形式,we were used to是省去that的定语从句,修饰the life。
2. The animals are kept in tiny cages and can hardly move at all.
[考例] (1) ─How clean and tidy your bedroom is!
─Thank you. It ______ every day.
A. cleans B. is cleaned
C. was cleaned D. is cleaning
(2) A report says hundreds of thousands of trees ______ in the Amazon(亚马孙河) rainforest last year.
A. was cut down B. have been cut down
C. were cut down D. has been cut down
(3) ─What should we do first if we want to develop our village?
─A lot of new roads ______, I think.
A. must build B. have to build
C. must be built D. have built |
