chia theo Thì quá khứ tiếp diễn fly = cry = see = Chia thì quá khứ đơn hoặc quá khứ tiếp diễn thích hợp 1.The aeroplane (catch)....... fire just when it (take)........... off 2.The lights (go).... out when we(discuss)......the plans for the following morning 3.Proesor Ward (give)...... the lecture when the students' riots (begin)  

Để chia theo thì quá khứ tiếp diễn, chúng ta thêm "was/were" vào động từ nguyên thể.

1. The aeroplane was catching fire just when it was taking off.
2. The lights went out when we were discussing the plans for the following morning.
3. Professor Ward was giving the lecture when the students' riots began.

Professor Ward was giving the lecture when the students' riots began

The lights went out when we were discussing the plans for the following morning

The aeroplane caught fire just when it was taking off

saw, seeing