ممكن الاجابة مع التوضيح choose
1- Mona was carrying two heavy bags. She .......... the shopping at the supermarket.
a) had done b) had been doing

2- He looked tired yesterday because he .......... badly the night before.
a) had slept b) had been sleeping

3- When .........., Ali was unhappy because he knew he was innocent.
a) arrested b) arresting