And as professor Von Heijne says, their understanding of the mechanisms at work has opened the door to others seeking new treatments.

VOA: standard.2009.10.07

I think I could maybe afford a front door if I work really hard for the rest of my life.

我想如果我下半辈子努力工作的话，我可以买得起一个前门。

怡人的的汉普斯特德 - SpeakingMax英语口语达人

And you're just entering the door after work.

你刚刚下班推开家门。

Don't 课堂 - SpeakingMax英语口语达人

House Speaker Pelosi agreed, saying Congress and the Obama administration must keep the door open to additional steps, even as the current stimulus plan begins to work.

VOA: standard.2009.03.10

If you don't like the way I work here,there's the door.

VOA: standard.2009.12.17