Would vs past simple

[ostap77]

A: If only people (not/throw) their garbage in the streets.

B:Frotunately, the town council is setting up an anti-litter campaign next month.

I would put "wouldn't throw" in brackets. I wonder if I could use "didn't throw" here?

[emsr2d2]

If you spell "didn't" correctly, then yes, you will hear that. "Wouldn't" is marginally more natural but "didn't" is fine.

In BrE, you would probably hear "drop", not "throw" and possibly "in the street" (singular).

[ostap77]

Which one would you use "wouldn't" or "didn't"?

[emsr2d2]

Probably "If only people didn't drop litter" or possibly "I wish people wouldn't drop litter".