Olympiad Test Level 1: Idioms & Proverbs

KEPT AN EYE ON means Closely observed.

In the end is used mostly as an idiom that means "finally," "after a long time," or, "when everything is considered."

Willing to do anything for the liking of someone or something.

However careful you try to be, it is inevitable that some unfortunate or unforeseen events will occur.

Crying over spilt milk is like feeling sorry for something that can't be changed.

It is better for somebody or something to be late than never to arrive or to happen.

Don't put all your eggs in one basket is a proverb that warns not to invest all of your resources into a single thing because you might lose everything.

Keep your friends close and your enemies closer.
Friends are to be kept close to oneself in order to enrich our lives. One would normally think of keeping the enemies away at a distance. However, in such a case, we may not be able to keep track of their plans. By keeping enemies (or malicious people) closer to oneself, it is easier to be vigilant and be aware of any plans which they may have to harm us. 

Two heads are better than one. For example, The company engaged with another marketing consultant because it is an important project and two heads are better than one.

Where there's smoke there's fire, they mean that there are rumors or signs that something is true so it must be at least partly true.