While Suzy ______ on the sofa, the phonerang.

he was investigating ways to improve the telescope,Newton made ________ discovery which completely changed ________ man’sunderstanding of color.

Then moment _________ Mary will always remember is _________ Mr. Black gave her a lot of valuable advice on how to improve her writing.

I have a meeting to attend. I have to go first.– It’s raining hard. until it stops or you will get wet.

We thought it was he who did it, but it _________ that he wasn’t even there.