Раскройте скобки и поставьте глаголы в правильную форму:
1. Не (tc call) the British firm from 10 till 11 o'clock tomorrow.
2. My secretary lost the keys when he (to walk) in the park.
3. When the Personnel Manager (to come)? - He (to come) 10 minutes ago.
4. Our Export Manager (to leam) English before he entered the University