切记

yù shì qiè jì yào zhèn jìng

遇事切记要镇静。

When something unexpected happens, you must always remember not to panic.

mā ma de dīng zhǔ nǐ yào qiè jì zài xīn

妈妈的叮嘱，你要切记在心。

You must never forget what your mother told you.

qiè jì guò qù de jiào xùn

切记过去的教训。

Never forget past lessons.