Heavy on the Highlight

There's this scene I remember from one of the many great Nickelodeon shows from the Nineties, The Adventures of Pete and Pete, where Big Pete is panicking about a test that he forgot to revise for. One of his mates offers him their text book to revise from, telling Pete that all the important bits are highlighted (highlit? *shrug*). Big Pete opens the book to find the whole freakin' thing is highlighted.

That's kind of how my Mandarin grammar notes are on the verge of becoming.