问题
填空题
1. Don't let him (go) there alone.
2. Have you finished (read) the book?
3. 
All the students are busy (clean) the room.
4. Did you hear the baby (cry) in the next room?
5. Jack went to school without (take) his backpack.
答案
1. go 2. reading 3. cleaning 4. cry 5. taking