_ is known to us all that the old scientist, for _______ life was hard in the past, still works hard in his eighties.

Make sure that your computer room is 100%________of insects because they can really cause trouble to your machine.

You see how thin Ann is!——She ______ gain some weight but she______ toolittle

Tommy is ________ not to get angry easily.

This soup is cold; it needs _____