The number of group names of several good old classmates after 70 is uncertain, depending on the specific situation and the number of students. Generally speaking, the post-70s students are mainly groups created based on social media platforms and instant messaging tools. The choice of group names can be named according to common interests, alma mater, class or other characteristics. For example, the "post-70 s alumni group of XX Middle School" or the "basketball fanatics" group that can reflect the same hobbies. The specific group name should be decided according to the opinions and preferences of the group members.