The verbal expression HIT THE BOOKS means to study or begin studying very intensely:
I must pass this exam if I want to apply for the job, so I’d better hit the books.
Mom, just let me play for one more hour and then I’ll hit the books, I promise.
I only have two months to learn Swedish, so I must hit the books really hard.
I think you didn’t hit the books hard enough. Otherwise you’d have passed the test.
All freshmen should hit the books right now. There’s quite a lot to learn in the first year of college.
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