Hi, I have a question in my mind for a long time-----
How to say sb. came just very in time when you need help?
The best expression to choose would depend, as usual, on the context in which it would be used.
Anyway, here are a couple of expressions that might help:
"You came just when I needed (your) help most."
"You came at the right moment; I was in need of help."
OK, Miriam’s covered it. Maybe a less formal approach could be
“you got here in the nick of time”
I read Disney comics – use at your own risk!
Students: We have free audio pronunciation exercises.
Now you make me think of a question: 'Could you get here in the nick of time?'. Would this be an appropriate question?
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Do be punctual darlin'