重点讲解：
1. a couple of
两个；几个；
eg. I've got a couple of questions I'd like to ask you.
我有几个问题想问你。
eg. The committee is going into recess for a couple of weeks.
委员会打算休会几个星期。
2. sweep up
扫除；清扫；
eg. He started working for a gallery sweeping up and making the tea.
他开始在画廊做扫地沏茶的工作。
eg. She was left to sweep up after the party.
聚会结束后她被留下来打扫。
3. dream of
梦想；渴望；
eg. As a schoolgirl, she had dreamed of becoming an actress.
她上学时曾梦想成为一名女演员。
eg. I did once dream of becoming the first woman to captain an ocean liner.
我确实曾经梦想过成为首位远洋客轮的女船长。