我想成功，但首先我要掌握英语。

I want to succeed, but first of all, I have to master English.

youdao

但首先我要，我想要知道。

But first I want, I want to know.

youdao

各位，在我们面前有很多要做的事情，但首先我要发表演讲，并参加庆功聚会。

We have a lot of work ahead of us folks, but first we have a speech to give and a victory party to attend.

youdao

All right. So, today we're going to be talking about molecular orbital theory, but first I wanted to just mention, in case some of you didn't hear what the Nobel Prize was this morning, and this was in chemistry, it went to three different chemists.

好的，今天我们要讲的是,分子轨道理论，但首先我要说，以免有些同学没有听到,今天早上的诺贝尔奖，这是化学奖，它颁给了3个不同的化学家。

麻省理工公开课 - 化学原理课程节选

But first, I just want to remind you when we're talking about molecular orbital theory, this is treating electrons as waves, so what we're actually able to do is either constructively or destructively combine atomic orbitals to form molecular orbitals.

但首先，我要提醒你们,当我们讨论，分子轨道理论的时候，我们把电子看作是一种波,所以我们可以相长叠加,或者相消叠加这些原子轨道来组成分子轨道。

麻省理工公开课 - 化学原理课程节选