Don't leave things half done. 做事不要半途而废。

　　I left the door open and she must have gotten out. 我没有关门，她肯定出去了。

　　It's not very good leaving candles unattended. 点燃的蜡烛如果不注意就不好了。

　　I'm going to bed soon.  我马上要睡觉了。

　　Leave the door to the bedroom open.  把寝室的门给我留着。