A close mouth catches no flies.

病从口入。

A constant guest is never welcome.

常客令人厌。

Actions speak louder than words.

事实胜于雄辩。

Adversity leads to prosperity.

穷则思变。

Adversity makes a man wise, not rich.

逆境出人才。

A fair death honors the whole life.

死得其所，流芳百世。

A faithful friend is hard to find.

知音难觅。

A fall into a pit, a gain in your wit.

吃一堑，长一智。

A fox may grow gray, but never good.

江山易改，本性难移。

A friend in need is a friend indeed.

患难见真情。