She left her children behind with a heavy heart.

　　她十分難過地丟下了她的孩子們。

　　She has ten years' useful experience behind her.

　　她有十年的經驗，能派上用場。

　　He's behind the rest of the class in reading.

　　他的閱讀能力不及班上其他人。

　　Your feet must be behind the line when you serve.

　　發(fā)球時你的腳必須站在底線的外面。

　　'There you are,' said a voice behind me.

　　“你來啦�！蔽疑砗笠粋�聲音說道。

　　He wasn't well, so we had to leave him behind.

　　他身體不適，因此我們只好把他留下。