What's wrong with this sentence

Is the sentence "English is spoken in all over the world." grammaticaly correct? Why or why not?

It isn't. The correct sentence is ""English is spoken all over the world."

The idiomatic phrase "all over" is usually used as an adverb. But in the sentence in question, "all over" is used as a preposition to mean "throughout." Thus...

"English is spoken in all over the world" is grammatically incorrect because two prepositions are being used in succession. That's a no-no. Pick one or the other ("in" or "all over", but not both).

Thank you so very much. I searched and searched "all over" the internet for help with this dilema. By the way, how do you know so much about grammar? I'm inquiring because eventhough I'm a native English speaker, I am trying to teach myself English grammar. So if you, or anyone else, know about any websites or books that might help me on my quest, please post (see, I probably used way too many commas in that sentence).

I'm no a native but it seems to me that the two first sentences shuld be connected by a comma instead of a colon.

You should know these things as a native speaker.

You should! You knew it was wrong when you heard it, right? Are you just looking for an exact reason?

The question was first asked by a non-native speaker. I then posted the question on this message board so that I wouldn't just tell her it was wrong but to also give her the exact reason as to why it was wrong.