've instead of "have" in present simple.

[flocosix]

Is it correct to say "I've" instead of "I have" in sentences like "I have no idea", aka present simple and other similar cases? - "I've no idea".
I think I've noticed people using it like that for a few times, but I'm not sure.

[English Freak]

As far as I know, you can't say "I've no idea.", because "have" is the main verb here not an auxiliary. So it's not possible to have the contracted form.
But, when "have" is an auxiliary, it's possible to have the short form as in "I've seen this movie several times." or "I've got no idea."

[Rover_KE]

'I've no idea' is commonly used informally and widely understood to mean 'I have no idea'.

Rover

[konungursvia]

Note that "I've" meaning "I have" is relatively rare in AmE.

[5jj]

As far as I know, you can't say "I've no idea.", because "have" is the main verb here not an auxiliary. So it's not possible to have the contracted form.
Wrong - as Rover has already said.

5

[billmcd]

Note that "I've" meaning "I have" is relatively rare in AmE.

Really? I've used it and I've heard it used many times.

[English Freak]

'I've no idea' is commonly used informally and widely understood to mean 'I have no idea'.

Rover

As you pointed out, it is used informally. And I don't know why 5jj confidently and strongly rejects my post in his. If I remember correctly, he himself once said something like this: "This site is usually visited by those who don't have enough knowledge of English ...". So I think it's better to guide them to the correct way. I didn't say it was totally wrong to say "I've no idea.", I just said "As far as I know ...". I just thought it was better to let them know the best and most correct way in formal English. And I'm sure everybody understands "I've no idea", but is it the best? Everybody will understand "I heart you" if you say that, but how correct is it grammatically?
By the way, according to what I've learned, it seems anything is possible in informal English.

[5jj]

I don't know why 5jj confidently and strongly rejects my post in his.

Because you wrote, 'you can't say "I've no idea.", because "have" is the main verb here not an auxiliary. So it's not possible to have the contracted form.' This is just not true. "I've no idea" is commonly heard.

So I think it's better to guide them to the correct way.

But you didn't.

I didn't say it was totally wrong to say "I've no idea.", I just said "As far as I know ...".

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You are welcome to reply to any of the questions posted in the Ask a Teacher Forum, even if you are not a teacher. In fact, your answers and contributions are most welcome. However, you will need to state clearly in your post that you are not a teacher. Please remember, the person whose questions you are answering or whose thread you are contributing ideas to believes the help is coming from a teacher.

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[Tdol]

I am going to close this thread as it is turning into a squabble. Please ensure that you guide people the correct way by showing them what is correct. Also, informal usage is in no way inferior to formal usage- it's not some depraved subset where ignorance and poor grammar reign.

Lastly, please try to stick to issues not personalities.