What does it mean to get married and write single happiness?

You can refer to the following possibilities. 1, the happiness of two people is the same, so we can be one, regardless of you and me. 2. Double happiness is connected with two horizontal lines, which are easy to separate. Single happiness contains you and me. 3. Personally, I can't separate and give up ... I can refer to it, play by myself, or borrow the above two, but the answer is wrong, she won't marry. ...