I heard his car start up.

我听见他的汽车发动了。

I went over to start up a conversation, asking her who she knew at the party.

我走过去攀谈起来，问她在聚会上都认识谁。

The project will require very little work to start up; that's the beauty of it.

这项工程几乎不需要启动工作，好就好在这里。

We have decided to start up a company.

我们已决定好开一家公司。

She surprised him several times by seeming to start up beside him as if she sprang out of the earth.

有几次，玛丽让他吃了一惊，因为这小姑娘神不知鬼不觉地突然出现在他身边，仿佛是从地底下钻了出来。