- after counting to a particular number:
On the count of three, run.
- when a particular number is reached:
On the count of three, I’d like you all to stand up.
On the count of three, they threw their grenades into the trench and ran.
We’ll both start at the same time. On the count of three - one, two, three, go!
The stage manager told the actors to stay backstage and, on the count of five, he’d wave them back on.
Stay calm - we’ll help you up on the count of three. Ready?