"You must be hungry after you jog for 2 hours."

[sky3120]

"You must be hungry after you jog for 2 hours."

I know that must is used for a current certainty, but I would like to know if must can be used for a future certainty like may, can, or must is never used for future situations? Thank you so much as usual and have a good and safe day.

Cf. He may become a teacher. ( a future possibility )

[5jj]

I know that must is used for a current certainty, but I would like to know if must can be used for a future certainty like may, can, ...

No

[sky3120]

Thank you, and then "You must be hungry after you jog for 2 hours." is wrong? Should it be "You will be hungry after you jog for 2 hours."

[Rover_KE]

Thank you, and then "You must be hungry after you jog for 2 hours." is wrong? Should it be "You will be hungry after you jog for 2 hours."

Yes—or better: 'You will be hungry after jogging for two hours'.

[sky3120]

Thank you so much and I found "After you finish filling out the form, you must send it in for it to be approved." But according to your explanation, shouldn't it be "...,you will have to send..." Or the sentence is okay to use? Thank you so much and take good care.

[Chicken Sandwich]

***** NOT A TEACHER *****

Or the sentence is okay to use?

The sentence looks OK to me.

[sky3120]

Thank you and then, "must" itself can imply future happenings?

[Chicken Sandwich]

***** NOT A TEACHER *****

I must call my mother tonight. I haven't talked to her in ages. Is this what you mean?

Take a look here to see how 'must' is used.

[emsr2d2]

Thank you so much and I found "After you finish filling out the form, you must send it in for it to be approved." But according to your explanation, shouldn't it be "...,you will have to send..." Or the sentence is okay to use? Thank you so much and take good care.

No. With "you must send it in ...", it is an obligation. If you do not send it in for approval, then nothing else will happen. You will have wasted your time filling in/out the form.

In "you must be hungry after jogging for two hours", it's a logical assumption. Imagine that it says "Wow. Surely, after jogging for two hours you are hungry?!"

[sky3120]

Thank you all and I am confused that I made my question unclear, so "After you finish filling out the form, you must send it in for it to be approved." is okay to use? I can't wait to hear from you again.