Put questions (1-general, 2-special, 1-tag,1-alternative). They were writing grammar exercises at 6 o’clock yesterday.
РЕШИТЬ!!

1 Were they writing grammar exercises at 6 o'clock yesterday?

2 Who was writing grammar exercises?

3 What were they writing?

4 Were they writing grammar exercises or doing phonetics?

5 They were writing grammar exercises, weren't they?