"We are getting married!"
要……了 is a set grammatical structure that indicates a near future and adds to the certainty of what is about to happen. 冬天要来了: Winter is coming (not much you can do about it, it will happen for sure and quite soon)
Thank you. Came here for this. Forgot the "要...了" structure and was wondering why it wouldn't be "我们会结婚"
Because they are going to get married. Without it, they have gotten married/are married.
I'm guessing 了in this sentence adds some kind of "finally" to this sentence, some kind of 'completion-feeling'. Can someone deny or confirm? My mother language is neither Chinese nor English so it's hard to explain. ^^
Guess number two: It is perfectly fine to not use 了. Actually, if you want to be literal and interpret the sentence as if the wedding is happening right now (as someone who's not native in english might think), you could remove the 了 and switch the 要 for a 在.
"Le" or "liao" indicates a change of state. Before the wedding, they are not married; after the wedding, they are :-)
It shows that they will be getting married, that it is a confirmed, soon to occur, incident. You have to use 了, without it the sentence expresses the desire of the couple who want to get married.