She realized her danger then, but could not seem to move.

Then, for the first time, he realized his danger, and started to run.

It was in her hand before he realized his danger.

I tried to make you realize the danger in what you're doing.

Didn't she realize the danger of being alone with him?

But by the time they realized the danger, it was too late.

You realize the danger they're going to be in if anything goes wrong?

When they realize the danger, it may be too late.

And the teachers would not realize the danger until it was too late.

The leaders of the two groups realized the danger and found a solution.