1. When you get in or get into a place, building, club, restaurant, meeting, and so on, you obtain permission to enter. When you get other people in or get other people into a building, club, restaurant, meeting, and so on, you arrange for them to enter.
2. When you get in or get into a place, you arrive. When the vehicle you are in gets in or gets into a place, it arrives. Come in is similar to get in.
3. When a store gets something in, it receives a delivery of something that it will offer for sale.
4. When you get an activity in, you find the time for it or make the time for it.

To secure a place in a college, university, etc.; SYN. get into.

1. When you get something in or get something into a place, building, room, container, enclosure, and so on, you get the object inside even though it is difficult.
2. When you get in trouble or get into a difficult situation or a mess (a mess is a confused or difficult situation), you become involved in it. When you get people in trouble or get them into a difficult situation or a mess, you cause them to become involved in it.

To establish communication with someone; SYN. touch base, connect.