Complete the sentences with the correct form of the verbs in brackets.

1. Don’t do too much. If you (run) too far, you (hurt) your knees.
2. He shouldn’t call the doctor unless he (feel) really bad.
3. When people (treat) themselves, it usually (not/work).
4. If your results (be) good, I (stop) your treatment next week.
5. The nurse (check) your temperature if you (think) you have a fever.