3.(1)Did go didn't did do went
(2)will do will-plant will plant
(3)are doing are-singing dancing are singing are-singing
(4)Did go didn't Did go didn't-go helped
(5)Does go does does shop
(6)came Did have leaved
（有连号的是在一个空中的）
4.(2)Did the boys visited the museum yesterday afternoon?
No,they didn"t.They visited the Great Wall.
(3)Did the boys visited the farm last Saturday?
No,they didn"t.They planted trees.
(4)Did the children watched a play last night?
No,they didn"t.They watched a film.
(5)Did the boy caught a bird yesterday morning?
No,he didn"t.He caught a fish.
(6)Did the girl cleaned her bedroom yesterday evening?
No,she didn"t.She watered the flowers.
5.Was was Where was with When was What How be did must See See
6.(1)Trees.
(2)Yes,they can.
(3)Yes,it is.
(4)It"s between two and three thousand years old.
(5)Harry Cole.
(6)It"s 113 metres tall.
追问我现在不用拉，这个问题有一年了，我现在是初中
时浑感谢！！