As a group owner, how to make the group active?

A group is a small society with a normal distribution. Some people are active, others don't like to talk, so we should actively explore those who prefer to express their opinions, so that they can form group dependence and chat in groups every day. Encouraging them to become group assistants can bring them some benefits, both verbally and practically. Slowly, a group of people will be eliminated, but there will also be fresh blood to join.