the question about "to"

Not quite clear what you mean. Can you give some examples?

Thanks, there are some examples.
1.I ask Frank to go shopping.(normal usage)
2.I apply computer to playing games.(use "to" as a preposition)

Your second example:



is not standard English.

I would write, "I use my computer to play games." or "One application of computer use is to play games."

Hi everybody, hi Noddy. Why not the gerund ?

Thanks, but I think there is still some situations use "to" as prepositions.
Am I correct?

navigator--

Gerunds don't use "to".

upstudio--

"Finally I was able to go to my desk to play some computer games."

Two infinitives, one preposition.

Thanks, there are some examples.
1.I ask Frank to go shopping.(normal usage)
2.I apply computer to playing games.(use "to" as a preposition)

In these situations we use <'for' + ing> and as Noddy noted your example is not idiomatic, meaning that it is not a collocation that a native speaker would use.

I [apply] use computers [to] for playing games.

I see, thank all you guys

In the sentence "I ask(ed) Frank to go shopping." the verb is actually "to go", not "to shopping".

Gerunds are not used with "to". If you find "to" and a gerund in the same sentence, you will find that the verb is "to (something)" gerund, not "to" gerund.

"I apply computer to playing games" is not a grammatical English sentence. "I use the computer for playing games" is a proper sentence, and so is "I apply the computer to game playing" (although this is awkward -- a native speaker probably wouldn't say it this way).

I'm frustrated. I don't know the grammar terminology to apply to this; I can only explain it using examples. I hope I have added clarity to this discussion rather than being more confusing!

After "to" the verb is an infinitive; unless "to" as preposition is included in the same grammatical structure; for instance: "To belong to" (here "to" is a preposition).

The sentence "I apply computer to playing games", "playing" is not a verb but an adjective.

I mean, games to be played.

Thanks.