Which one's is Correct?

[Sara]

Hello Teachers in this lovely web

Why do we say "When do you fly back to New York?" instead of "When will you fly back to New York"?

Thanks a lot

Sara

[Mister Micawber]

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Hi Sara,

Both questions are possible. If we use the present simple tense for a future event, we are usually presuming that it is an established fact-- the ticket has been purchased, there is no other possibility but that the other person will make the flight.

When do you start school next year?
I start on March 1st.

We can't have lunch next Friday; I see my doctor then.
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Native English teacher at Mister Micawber's

[Nicole]

Hi Mister Micawber,

Thank your for your explanation, but what about using present continous to express future plans? What about this sentence:

Next week I'm flying to New York.

Isn't that also a plan?

And what about the going-to future? What is the difference between these sentences:

Next week I fly to New York.
Next week I'll fly to New York.
Next week I'm flying to New York.
Next week I'm going to fly to New York.
Next week I'll be flying to New York.

Very confusing to be honest that's why we'll greatly appreciate your help.
Nicole
_________________
Life is for living.

[Mister Micawber]

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It's a long story, Nicole. It would be easier if you just got a copy of Michael Lewis's The English Verb.
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_________________
Native English teacher at Mister Micawber's

[Guest]

Thanks a lot Mister

Best Regards

Sara