gene
基因  

例句：
The geneticists were not interested in particular genes until recently.
直到最近，基因学家们才开始对特定基因感兴趣。
 

blunder upon…
偶然碰上……
 
例句：
Yesterday I blunder upon an old friend I hadn't seen for several years.
昨天我偶然碰上了一个几年没见面的老朋友。
 

Don't jump to conclusions.
不要急于下结论。

对话：
A: This book isn't worth reading.
B: Don't jump to conclusions. You should at least skim through it.
A: Maybe you are right.
　
A：这本书不值一读。
B：不要急于下结论。你至少应该浏览一下。
A：也许你说得对。