How do you use weave and we've in a sentence?

Answer 1

"we've" is an abbreviation of "we have", so you would use it where you would use "we have".

-------

We've bitten off more than we can chew in redesigning the garden.

------------------------------------------------------------------------------------

"weave" is a word relating to fabric or strands, a "weaver" is someone who "weaves" cloth and when you are examining the cloth you could admire its "weave".

-------

I just got purple weave in my hair.

Answer 2

"Weave" is the present tense verb meaning to create a fabric by interlacing threads. (e.g. She learned to weave a beautiful tapestry.) "We've" is the contraction for "we have." (e.g. We've been friends for many years.).