Emergency line operators must always _____ calm and make sure that they get all the information they need to send help.

It’s obvious that the Beijing Olympic Games       a great success．
A．kept      B．showed       C proved     D．remained

Scientists ____ thousands of chemicals before they decided on the right one in the end.

As is widely acknowledged, a great number of traffic accidents ____ numerous deaths and countless property loss all over the world every year.   

Books of this kind       well.

Being afraid of falling behind the times, he has always been keeping himself ___ of the latest development of technology.
A. instructed    B.  intended    C.  informed   D demanded

The class __________ 80 students is hard to manage.

We had a really bad time about six months ago but now things are______.

Rather than            boring TV shows, he always prefers             original novels

--- I was wondering if we could go skiing on the weekend.
--- ______ good.