English for Today by Ganiu Abisoye Bamgbose (Dr GAB)
MIND THE S’s
He knows the ~in and out~ of the ministry (nonstandard).
He knows the *ins and outs* of the ministry (standard).
The detailed or complicated facts of something are the ins and outs of such thing.
Note that this is different from being in and out of somewhere:
She has been ~ins and outs~ of school since January (nonstandard).
She has been *in and out* of school since January (standard).
I gave him money today so I’m still in his ~good book~ (nonstandard).
I gave him money today so I’m still in his *good books* (standard).
When you are in someone’s good books, they are pleased with you. Note that “the book” is also used to refer to the Bible in American English.
GAB
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