doze off

• (无意之中)打瞌睡，打盹儿：

  The film was so boring that I dozed off in the middle of it.

  那部影片很乏味，我看了一半便打起瞌睡来了。

  The boy dozed off while his mother was reading to him.

  男孩的妈妈念书给他听时，他打起瞌睡来了。