重點講解：
1. clear one's throat
清嗓子；
eg. Cross cleared his throat and spoke in low, polite tones.
克羅斯清了清嗓子，開始有禮貌地低聲說話。
eg. I have to clear my throat before I begin my speech.
在開始演講之前，我得先清清嗓子。
2. proceed to do sth.
接下來做；接著做某事；
eg. We shall proceed to show that it was this which the Austrians were looking for.
我們將進一步表明，它就是奧地利人想尋求的東西。
eg. We now proceed to investigate the method of components concerning vector.
現在我們接著研究關于矢量的分量法。
3. line up
（使）（某一批人）排成行；（使）列隊；
eg. At 10 o'clock people began to line up for the tickets.
10點鐘時，人們開始排隊買票。
eg. Please line up at the starting line for the three - legged race.
請參加兩人三足的快點到起跑線準備。