留心 (liú xīn) — to be careful; to pay attention; to keep an eye on

Definition

Examples

• 你过马路的时候一定要留心。
  Nǐ guò mǎ lù de shí hou yí dìng yào liú xīn.
  You must be careful when crossing the street.
• 这件事很重要，你多留个心。
  Zhè jiàn shì hěn zhòng yào, nǐ duō liú gè xīn.
  This matter is very important; keep an extra eye on it.
• 上课的时候要认真听讲，多留心。
  Shàng kè de shí hou yào rèn zhēn tīng jiǎng, duō liú xīn.
  During class, you should listen attentively and pay close attention.

Origin