But let me warn you first.

让我先警告你。

youdao

When did you first play on your own?

你第一次独自演奏是什么时候？

youdao

When did you first meet him?

你和他初次见面是何时？

《牛津词典》

The answer is yes. However, you first must take the steps necessary to protect yourself and your family from the dangers of the sun.

VOA: special.2010.07.06

Wait. Don't you first need to study the other ?" so that you can be more sensitive to others?"

等等，你难道不要首先研究别人,才能对别人更敏感吗“

哈佛公开课 - 幸福课课程节选

What are some things that you noticed when you first came to Berkeley?

当你第一次来伯克利的时候，你注意到了一些什么事情呢？

伯克利的特点 - SpeakingMax英语口语达人

You said a pimple, something like that, does that what it looks like when you first get it?

NPR: Tracking a New Strain of Drug-Resistant Staph

In order to grow a "green" economy, you first have to have an economy.

FORBES: New Geographer

When you first use Pokki the service installs a Pokki icon on your desktop.

FORBES: Pokki Brings Mobile-Style Apps To Desktop PCs