Student or Learner
In the following sentence, why we have to use move not moving?
Iíll give you my phone number after I move house next week.
Here, I think you meant "after I am moving" or something like that.
"To be moving" is the continous form, which stresses the process.
But the phone number will be given after the move is complete.
This should mean that a perfect tense is required, and indeed the pedant would say "I will give you my phone number after I shall have moved house next week."
But in practice, the perfect tense is omitted; the simple form is enough, since it doesn't stress the process and therefore implies the completion, especially in the future (the future perfect forms are quite formal).
And here it is idiomatic to use the present to mark the near future.
So it's "Iíll give you my phone number after I move house next week."