He apologised to me for his ________ my letter．

You shouldn’t keep silent when __________．

---What’s your impression of the Great Wall?
---Wonderful! Once ____ , it can never be forgotten.

____ that you are chosen to be a volunteer at the London Olympic Games, what will you do?

--- What do you think made Ceha so happy?  ---        a prize in the recent competition.

______me, he walked up to me, smiling.

From his _______ look, we could see that he hadn’t expected that we could raise such _______ questions to him.

I saw Tom ______ into the classroom without ______.

The officers narrowly escaped ___________  in the hot battle.

She was scared _______ when hearing the sound of explosion.