Not until

[Belly T]

The refugees continued to feel unsafe until they had crossed the border
My teacher corrected the answer using Not until
Not until the refugees had crossed the border, did they feel safe
Why we have to change it from 'safe" to unsafe?

[rewboss]

The original sentence describes how the refugees felt before they crossed the border.

Your teacher's version describes how the refugess felt after they crossed the border.

Notice how in each sentence there is one negative. In your version, the negative is the "un" in "unsafe"; in the teacher's version, the negative is the word "not".

[dihen]

Can I say?:
`
Until the refugees had crossed the border, they did not feel safe.

[MikeNewYork]

Originally Posted by dihen

Can I say?:
`
Until the refugees had crossed the border, they did not feel safe.

Yes.

[Belly T]

But "not until" use as meant before, too?