Are these sentences correct?/...you had better think again/ in one hour's time

English as a Second Language English Vocabulary, Grammar and Idioms
1

Hi everyone,

Can you say: (1) ‘If you think I appreciate you flattery, you had better think again!’

Can you say:(2) 'I would like you to do your homework in hour’s time.

Thanks
Alexandro

2

Hi,

(1) is fine.

(2) needs to be ‘in an/one hour’s time’.

Alan

3

Thank you so much Alan!

4

Teacher Alan, I’d like to ask you a question because this is not clear to me.
Why “hour’s” and not “hour”? Thanks

5

Hi,

This is the time/duration of one hour.

Alan