1、,Unit 4 Cartoons and comic strips,第3课时语法,This pair of trousers should not be washed again.,Should the water be cleaned before we drink it?,Yes, it must.,No, they cant.,Those books must be taken back to the library.,Children can be taken to the cinema by their parents,on Childrens Day.,The children h
2、avent been looked after well.,Have lots of tall buildings been built in his hometown,in the last three years?,Yes, it has.,No, they havent.,A lot of trees have been planted by them since 1990,The novel has been read twice by my father since he,bought it last month.,C,B,B,A,B,B,B,B,C,A,was brought,will be finished,be shown,are not allowed,has been done,be returned,be put,has been raised,be spoken,be thrown,B B C C B,A C B B C,but,laughing,a,late,to make,of,funny,shown,success,that,
