1) am not drinking, am writing
2) don't drink,
3) is your friend doing his homework now
4) went
5) is sleeping
6) sleep
7) doesn't working
8) isn't sleeping, is working
9) get up
10) what is your sister doing now? Is Washing
11) when do you usually come home? Come
12) where does your constant work? Works
13) does your sister study at an university? Study
14) go to
15) isn't playing, played