1. We've been going out for quite some time now.
This is said as aprecursorto something else.It can be a good warm up sentence to tell your partner that you're madly in love with them.
2. I think we have something really special.
"Something special" refers to a special relationship or feelings.You would only say this to a girlfriend/boyfriend, not to a platonic friend.
3. I want to settle down.
"To settle down" in this context means to settle down with your lover.This is used to give a sense of stability in the relationship.
“to settle down”在上下文中意思是和你所爱的人一起安定下来，让你们的关系增添稳定的因素。
4. You are my soul-mate.
Your "soul-mate' is someone that you have a deep and intimate friendship with.a soul-mate is also a lover, someone that you have a strong emotional or spiritual bond with.
你的“soul-mate”是指某个与你关系很深、很紧密的人。他可以是情人，那个你有强烈感情或在精神上结合在一起的人。如果你还没有“soul-mate”，就可以对自己说：“OK, where is my soul-mate?”
5. I'm ready for a life-long commitment.
"A life-long commitment" means that you want to spend the rest of your life with someone.pretty serious, huh?
“a life-long commitment”，说出这句话，可就意味着你打算与某人相伴共度余生。
6. Let's tie the knot!
Alternative sentence: "let's get hitch!" Both of these sentences are light hearted and humorous ways to suggest marriage.Of course, the traditional way to "pop the question" is to ask "will you marry me?"
这句话可以换一种表达方法：“Let's get hitch!”这两句话都是用一种轻松幽默的方式去建议结婚。当然啦，用传统的方式去pop the question你可以说“Will you marry me?”（你愿意和我结婚吗？）