1. has been practicing
2. have they eaten
3. haven't cleaned
4. have been working
5. has seen
6. have been traveling
7. have you swum
8. has been playing
9. have you been studying
10. have you been doing/haven't done
1. has been practicing
2. have they eaten
3. haven't cleaned
4. have been working
5. has seen
6. have been traveling
7. have you swum
8. has been playing
9. have you been studying
10. have you been doing/haven't done