the different between "to call" and "calling"

Hello, Lynn!

To me, "I forgot calling you" means that the person doesn't remember the fact that s/he actually called the other person.

"I forgot to call you" means the "I" didn't call the "you" because it slipped out of his/her mind.

Hi! Pieanne,

How can you tell that?

Lynn

Hello, Lynn!

In the first sentence, "forget" is synonym to "not remember"; I focused on the -ing or to+inf form, so the sentence would be better: "I've forgotten ever calling you", meaning "I don't remember ever calling you". I don't have any such memory.

"I forgot to call you (last night)" means that I was supposed to call you, but it slipped off my mind.

Hello everybody,

This question has been already answered. This is a general rule that I find very useful.

Hi!

I feel that it is so hard for me to remember the two different situation by heart. Do you have any easy way for me to remember it?

Thanks,

Lynn

Well, maybe you could think that "to" implies some projection into the future. "Don't forget to buy some bread" means that at some moment in the future you'll have to think of buying it. If I think of something else, I'll tell you!

To my BrE ears, "I forgot" + gerund isn't idiomatic.

If you want to say that you did not call someone because you didn't remember, you say "I forgot to call you".

If you want to say you have forgotten the act of calling someone, you say "I forgot (the fact) that I'd called you".

"I'll never forget" + gerund is fine.

MrP

My ears must be partially British, because your observations, Mr. P., match my AmE intuitions exactly.
CJ

Sorry... My mistake!

Thanks, CJ - after a few months here, you start to wonder whether even the strangest combination is standard somewhere in the world.