A family is a very close and related unit of people, so we refer to it as single. Example: Our family is going to Florida for vacation. My wife's family lives in Denmark. I once knew a family that was so generous they gave away all their Christmas presents to under privileged people at the local homeless shelter. Couple, is mostly plural, because we are talking about two people. Example: That couple looks very much in love. They have not stopped staring at each other or holding hands for the last 2 hours. We are going bowling tonight with a couple who are friends with my wife. There are cases however, when couple can be used as singular. Example: That couple is the most attractive couple at the dance. We only refer to a couple as a singular unit when we are describing both people as if they were one entity.

The words family and couple are examples of "collective nouns". These are nouns that are considered as singular because they act as ONE UNIT. So you have to use the auxillary verbs or linking verbs such as is or was. Example: The family is happy. The couple are exercising. The only time you consider these nouns plural is when you refer to every member of the group. Example: 1. The family are happy. (Here you are referring to each and every member of the family.) 2. The couple are exercising. (Same as the idea in the sentence above, you are referring to both person individually) another example of this that can show you the desciption clearer is... 2a.The couple are on the treadmill and elliptical exercising. (Here you see that they are doing separate activities) Good luck Raul! Hope this is clear for you

singular