Điền thì thích hợp của từ:

1. keep silent! the teacher (explain) ____________ the lesson
2. at present, we (do) ________________ exercies
3. they (play) _____________ badminton at the moment?
4. my mother (cook) _____________ dinner now
5. the farmer (plough) ______________ the field
6. ___________ these children (draw) _____________ pictures?
7. look! the dog (run) _____________ 
8. Nam (sit) ______________ next to the window now 
9. Nam and Ba (wash) ______________ their bicycles at present
10. _____________ you (sleep) _____________, Nga
11. I (not study) ______________ at the moment
12. Hoa (water) ________________ the flowers at present 
13. we (not help) ______________ our parents now
14. _____________ Lan (tidy) ______________ the room now?
15. Ba (not play) _____________ games now
16. Ba and Nam (study) _____________ English at present
17. _____________ you (listen) _________________ to music now?