I wanna (want to) be with you forever.
或者:
I wanna always be with you.
还有一种说法就是:
I want to spend the rest of my life with you. (我想跟你过一生)
i want to stay with you forever
I wanna share my life with you.
我想永远和你在一起.
I wanna be with you forever,Jack.
I wanna be with you for the rest of my life.
I want to stay with you forever
I wish to stay with you forever.