Question

Поставьте глаголы в скобках в Present Simple, Past Simple, Future Simple, Present Continuous, Past Continuous.
2. At the age of twenty my father (to combine) work and study.
3. What you (to do) at five o'clock yesterday?

Answer 1

2. At the age of twenty my father combined work and study. (Past Simple)
3. What were you doing at five o'clock yesterday? (Past Continious) 

Answer 2

2.  At the age of twenty my father combined work and study.
3. What were you doing at five o'clock yesterday?