get something across/ over means communicate, make understandable (e.g. I tried to get my point across/over to the judge but she wouldn’t listen.)
get along/ on means like each other (e.g. I tried to get my point across/over to the judge but she wouldn’t listen.)
get around means have mobility (e.g. My grandfather can get around fine in his new wheelchair.)
get away means escape, leave with difficulty (e.g. We tried to catch the thief, but he managed to get away)
get away with something means do something wrong without being caught (e.g. I parked in a no-parking zone, but I got away with it)
get back at somebody means retaliate, take revenge (e.g. My sister got back at me for stealing her shoes. She stole my favourite hat.)
get back into something means become interested in something again (e.g. I finally got back into my novel and finished it.)
get back means return (e.g. We got back from our vacation last week.)
get back to somebody means reply to them by phone etc. (e.g. I sent him an email, but he never got back to me)
get something back means receive something you had before (e.g. Liz finally got her Science notes back from my room-mate.)
get by means manage (e.g. My French isn’t very good, but it’s enough to get by.)