I.
2. have to work
3. has to practice
4. has to stay
5. have to help
6. have to go
II.
2. Do....have to
3. does...have to
4. Does...have to
5. do..have to
III.
1. should
2. should I
3. should
4. should I
5. shouldn't
IV.
1. burn
2. bites
3. cut
4. broken
5. bruise