[Grammar] I would appreciate

[Offroad]

Dear teachers

Would you please give your opinion on the correctness of the sentences below?

I would appreciate it if you could help us.
I would appreciate it if you would help us.
I would appreciate it if you helped us.

Thanks

 

[redcrows]

I would appreciate if you could help us.
I would appreciate if you would help us.
I would appreciate if you helped us.

Usually you must appreciate something...for example:
I would appreciate your help. "your help" becomes "it".

I would appreciate "it", if you could help us.
I would appreciate "it", if you would help us.
I would appreciate "it", if you helped us.

then all of these sentences make sense...