人教版九年级下册英语Unit 13 Section A长江作业本答案
1Unit 13 Section A第一题答案
1、water pollution，air pollution，waste pollution，noise pollution
2、（1） am／is／are+现在分词构成
（2） have／has+动词的过去分词
（3）助动词be+及物动词的过去分词
（4）情态动词+be+及物动词的过去分词
2Unit 13 Section A第二题答案
Ⅰ、
1、used to do
2、play a part in
3、cut down air pollution
4、instead of
5、keep public places clean
Ⅱ、
| 6 | 7 | 8 | 9 | 10 |
| D | C | D | C | B |
Ⅲ、
11、What；to do
12、didn't there
13、Is；anything
14、was painted
15、took a bus
3Unit 13 Section A第三题答案
Ⅰ、
1、hear of
2、cut off
3、so far
4、be harmful to
5、not only. . . but also. . .
6、bring danger to
7、the number of
8、no longer
Ⅱ、
9、NVithout；no longer
10、drop too low；ocean life
11、So far；have shown
12、taken part in
13、heard of
Ⅲ、
14、The place was not only cold， but also humid
15、We can't afford to go abroad this summer.
16、The number of students in this class is 50.
17、I understood this sentence by asking my/the teacher for help.
18、Smoking too much is harmful to his health.
19、We should ride our bikes or walk to school instead of driving.