fall behind ( falling, fell, fallen, falls )

• 1. 

  PHRASAL VERB If you fall behind, you do not make progress or move forward as fast as other people. 落后于

  例：

  Boris is falling behind all the top players.

  鲍里斯正落后于所有的顶尖选手。

• 2. 

  PHRASAL VERB If you fall behind with something or let it fall behind, you do not do it or produce it when you should, according to an agreement or schedule. 拖后

  例：

  He faces losing his home after falling behind with the payments.

  他拖欠还款后面临失去住房的问题。

  例：

  Thousands of people could die because the relief effort has fallen so far behind.

  成千上万的人可能会因救援跟不上而死去。