请教：
"select over"什么意思？
科技英文：
...the compounds with formula I should be selected over compounds with formula II.
式I 化合物选自式II化合物吗？还是 式II化合物选自式I化合物？
老外是不是说话也常常不严谨？打错介词？
谢谢先！
>>>>>
To select over is to choose in preference to.
This sentence tells you that formula I is better than formula II.
