It is rare for two people to be able to finish each other's sentences, but it does happen with couples who have been together for decades. Sometimes, this occurs when they have only been together for a few years, and this is because they are in complete harmony with each other. Couples like this often spend a great deal of their time talking about their beliefs, goals and opinions. Each one takes the time to listen intently, and they remember what their partner has said.
The hurry up and wait attitude of the modern world has taken away the time many couples have to spend with each other. Digital devices claim their attention at home, and errands are many and time-consuming. Spending the time to talk about their day or the world around them has become a thing of the past for many, but couples who truly want to finish each other's sentences will make the time to be together.