In fact, there are tons of them, it depends what meaning you want to express. Some of them are a little strange and can be out of fashion, so you need to notice what situation you are. Here is a one I like, "Act your age, not your shoe size", it works more in America, European size doesn't fit very well :) Here are some sources for you to reference: The more British ones: http://www.bbc.co.uk/worldservice/learningenglish/language/theenglishwespeak/ The more American ones: http://esl.about.com/od/glossary/Glossary.htm

There are thousands. Everyone will have their own favourites. I would recommend an Idiom dictionary, or you can download an Idiom and Phrases dictionary for free if you have a smart phone (search the app store). You can try learning one or two a day and practising them in conversation. One warning: idioms are clichés, so they are fine for conversation, but they should be avoided if you're writing essays, articles, letters, formal emails, etc.

This might be helpful... http://en.wikipedia.org/wiki/List_of_English-language_idioms

maybe Chinese idioms