重点讲解：
1. focus on 集中（注意力）；关注；
例句：When you are trying to focus on what you are reading, you need to be in a comfortable seat in a quiet room.
当你正在全神贯注的阅读时，你需要坐在一个安静的房间里的舒适的座位上。
2. aim to do sth. 致力于；旨在；以…为目标；
例句：He aimed to surprise his friends.
他想要让朋友们惊喜一下。
3. set up 创建；建立；安排；组建；
例句：We are planning to set up a publishing house.
我们正打算建立一家出版社。
4. be expected to do sth. 预期；预料；
例句：He said the plant`s initial production of iron sponge is expected to reach 230, 000 tons a year.
他说这个厂的最初期海绵钢产量预计达到一年230,000吨。
5. serve as 用作；可当…使用；充作；
例句：They drafted him to serve as their delegate.
他们选派他作他们的代表。
6. step up 增加（数量等）；提高（速度、强度等）；
例句：It was enough to make Joe step up his roadwork from three to five miles every morning.
这足以使乔把每天早上3英里的长跑增加到5英里。