.Since we have failed many times, why not take  a new _________to solving the problem?

Finding a job is very difficult, so the forst_____ is very important in a job interview.

Before the final examination, many students have shown ____ of tension. Some have trouble in sleeping while others have lost their appetite.

There are 40 students in our class，who come from a  ________of backgrounds.

Although I had read the book assigned by the professor several times, it didn’t make any______ to me.