1、But if scientists happen upon pure fusion, who knows what they might do with it?
但是如果科學(xué)家開啟上面的純核聚變反應(yīng)堆，誰知道他們可能會(huì)用它來做什么？

2、Our heroes happen upon a Bug pokemon Catching Contest.
我們的英雄時(shí)發(fā)生錯(cuò)誤神奇寶貝趕超競(jìng)賽。

3、happen upon sb. in the street
在街上偶遇某人

4、How do you happen upon these subjects?
您是如何想到這些主題的？

5、Luck doesn't just happen upon us.
運(yùn)氣并不會(huì)碰巧降臨在我們身上。

6、Luck doesn't just happen upon us-it comes to us when we're open.
運(yùn)氣并不僅僅發(fā)生在：當(dāng)我們打開它涉及到我們。