1. A buyer could maximize utility but he
prefers to have less rather than more. (Past Simple)
2. We shall have to know the
effect of a price change on the whole output for making economic
forecasts. (Future Simple)
3. The consumer had to solve the problem of
choice. (Past Simple)
4. Not all partners in a firm had to take an active
part in management. (Past Simple)
5. Provided additional inputs will have to be
obtained, producers must have smaller risks of a fall of price. (Future
Simple)