. In our class, when the bell rang and the teacher closed his book, it was a ______for everyone to stand up.

The new teacher made a good ____ on the students by her rich knowledge and humorous talk.

There is reason to believe that most writers have difficulty in ______ the opening paragraphs of their papers.

When Jane began to take swimming lessons, her main ____ was the fear of water．

---What’s the chief ______ of the world this year?---I think the Twin- Tower was destroyed.