3. Complete the text with the Past Simple or Past Continuous forms of the verbs in brackets. It was a warm day. The sun was shining (shine) and the birds ___ (sing) in the sky. Suddenly, the explorers ___ (hear) a strange noise in the forest. They ___ (not know) what it was. So, what ___ (they / do)? They ___ (run) back to the car.

It was a warm day. The sun was shining and the birds were singing in the sky. Suddenly, the explorers heard a strange noise in the forest. They didn’t know what it was. So, what did they do? They ran back to the car.

Past Continuous используется для длительного фонового действия, а Past Simple — для отдельных завершённых событий.