重点讲解：
1. break down
分解；将…分成若干部分；
eg. The report breaks down the results region by region.
报告将调查结果按地区分成若干部分。
eg. These rules tell us how a sentence is broken down into phrases.
这些规则告诉我们一个句子是怎样分解成若干短语的。
2. It's time to do sth.
句型，表示“是做某事的时候了”；
eg. Since we've been working so hard I think it's time to call it a day.
我们已经工作那么辛苦了，我想今天该停工了。
eg. We made a great deal of money, so we decided that it was time to set sail for home.
这使我们大赚了一笔，因此决定该是起程回家的时候了。
3. show up
如约赶到；出现；露面；
eg. We waited until five o'clock, but he did not show up.
我们一直等到了 5 点，但是他始终没有露面。
eg. If I don't show up for class this morning, I'll be kicked out.
如果我今天上午不去上课，我就要被开除了。