When you get over something, you recover from it.
EG: He was seriously ill, but now he got over it and he is very healthy.
When you just get by, you barely manage to survive (usually from the money you make).
EG: He doesn’t earn a lot of money in his new job, but at least he gets by.
When you get on with somebody, you are friendly with this person; you like him/her.
EG: He gets on very well with his cousin; he is his best friend.
When something gets you down, it depresses you.
EG: Every time I hear about young people dying, it gets me down.
When you get round to do something, you find time in order to do it.
EG: Women who work should get round to do both the house cleaning and the cooking.
When you get something across, you express your ideas to another person.
EG: She wanted to get her message across, so she wrote a book.
When you get away with something, you do something bad and you manage no to be punished about it.
EG: Everyone knew he had killed his wife but nobody could prove it; unfortunately, he got away with murder!
When you give something away, you donate it.
EG: She gave away all the old clothes she wasn’t wearing anymore.
When you give up, you quit.
EG: Children that do sports from a young age learn not to give up easily.
When something goes by, it passes (usually used with years).
EG: As the years go by, he realises that his parents are not going to be here for ever.