Gwynne's Grammar: The Ultimate Introduction to Grammar and the Writing of Good English [1] is an amusing overview of English grammar that provides bite-sized lessons that don't shy away from the irreducible complexity of English without becoming overly pedantic.

I also like A Student's Grammar of the English Language by Sidney Greenbaum and Randolph Quirk. [2] It is a difficult book, but the subtle taxonomies used in linguistic study actually make sense of matters that are confusing if you only know the type of grammar usually taught to non-specialists in middle or high school.

[1] https://www.amazon.com/gp/product/038535293X/ [2] https://www.amazon.com/gp/product/0582059712/