2. Complete the sentences. Поставь глаголы в скобках в форму Past Perfect Continuous: 1) Before the experiment ended, the scientists ____ (work) for six hours. 2) He ____ (study) mathematics since he was a child. 3) They ____ (test/use) the new method for long. 4) ____ she ____ (write) her report before the meeting?

Перевод задания: Дополните предложения, поставив глаголы в форме Past Perfect Continuous.

1. Before the experiment ended, the scientists had been working for six hours. — До окончания эксперимента учёные работали уже шесть часов.
2. He had been studying mathematics since he was a child. — Он изучал математику с детства.
3. They had been testing the new method for long. — Они долго испытывали новый метод.
4. Had she been writing her report before the meeting? — Писала ли она свой доклад до собрания?