is the reason for/subject/object

[navi tasan]

Which are correct:

1-Pollution is the major reason for leaving this city.
2-Pollution is the major reason that people leave this city.

3-Infidelity is the main reason for filing for divorce.

4-Committing a foul is the main reason for sending off a player.

Gratefully,
Navi.

[emsr2d2]

Which are correct:

1-Pollution is the major reason for leaving this city.
2-Pollution is the major reason that people leave this city.

3-Infidelity is the main reason for filing for divorce.

4-Committing a foul is the main reason for sending off a player.

Gratefully,
Navi.

If you want 1 and 2 to mean the same thing, then use 2. It's much more natural.
3 is OK but again, it would be better to personalise it with "Infidelity is the main reason people file for divorce".
I don't like 4. It almost sounds as if the referee is the one who commits the foul, or at least it doesn't make it clear who committed the foul. "Committing a foul is the main reason players get sent off" is much clearer.

[eunice65078]

#1 might be correct in some cases, but #2 is clearer that it is people who are leaving (not animals, businesses, etc?) - also "that" in #2 could be deleted since it is understood by the structure of the sentence. I am not a teacher, but speak and write English professionally...

#3 is correct sentence structure and so is #4 - but for #4 an American would probably say "committing a foul is the main reason for benching a player" or "the main reason a player is /would be benched ...