Tôi phải về trước.

I have to leave first.

Breakdown of Tôi phải về trước.

• tôi: I
• phải: have to
• về trước: to leave first

Questions & Answers about Tôi phải về trước.

What does each word in Tôi phải về trước do?

A natural breakdown is:

• Tôi = I
• phải = must / have to
• về = go back / go home / leave
• trước = first / earlier / before others

So the structure is basically:

subject + modal verb + main verb + time/order word

That is why Tôi phải về trước means something like I have to leave first or I have to go home earlier than the others.

What does phải mean here exactly?

Here, phải shows necessity or obligation. It is stronger than should.

So:

• phải = must / have to
• nên = should / ought to

In this sentence, phải suggests that the speaker does not really have a choice, or at least feels they do not.

Also, phải can mean other things in other contexts, but in Tôi phải về trước, it is clearly a modal verb meaning must / have to.

Does về mean go home or go back?