Ответ:

1. Hello! Where are you going? 2. I am just taking a walk. 3. Will you go to Great Britain next year? 4. Yesterday Nick said that he had read much during his summer vacation. 5. At the age of twenty my father combined work and study. 6. A great number of students were studying in the reading room when I entered it last night. 7. I will do my homework tomorrow. 8. I was doing my homework yesterday at 6 o’clock. 9. I had done my homework by 6 o’clock tomorrow. 10. I was writing a composition the whole evening.  

Объяснение:

Зависит, 1 – where – настоящее длительное, 2 – just – настоящее длительное, 3 – next year – будущее простое, 4 – yesterday – прошедшее простое, during – прошедшее совершенное, 5 – at the age of twenty – прошедшее простое, 6 – when – прошедшее длительное, last night – прошедшее простое, 7 – tomorrow – будущее простое, 8 – yesterday at 6 o’clock – прошедшее длительное, 9 – by 6 o’clock – прошедшее совершенное, 10 – the whole evening – прошедшее длительное.