Be in/get into somebody's good/bad books informal
If you are in/get into somebody's good/bad books, you have/not have their favour.
All you have to do to get into his good books is to follow what he requires.
Mary will not invite me to her party on Sunday because I'm in Jenny's bad book.
Have a strong feeling of affection for someone or something
To give someone or something better treatment than others.
A subject one knows a lot about, or likes a lot
The verb "be" and "get" should be conjugated according to their tense.
To punish someone or something harshly
He's a really strict teacher, so he'll definitely lower the boom on you if you don't do your homework.