Mixed tense sentence + When clause?

Question

Is it legal to write something like this: > When I'm trying to post a form system alerts me with a warning message. I've seen people use this kind of writing.

Answer 1

This sentence is close, but not 100% correct. I think what you're going for is "The system alerts me with a warning message when I try to post a form." What you have "When I'm trying to post a form system alerts me with a warning message. I've seen people use this kind of writing." forces the two clauses together unnaturally. You could also form your sentence like "When I'm trying to post a form, the system alerts me with a warning message."