Nǐ bùnénɡ yǐmàoqǔrén.

你不能以貌取人。

You can't judge a book by its cover.


Notes:

你(nǐ): you

不能(bùnénɡ): can't

以(yǐ): with

貌(mào): appearance

取(qǔ): to judge

人(rén): person, people

Example：

A：我不喜欢他。

     Wò bù xǐhuān tā.

     I don't like him.

B：你不能以貌取人。

     Nǐ bùnénɡ yǐmàoqǔrén.

     You can't judge a book by its cover.