How long ___he____ the library book.

How long ___he____ the library book. How long have you kept the book borrowed from the library How long can I keep the library book?为什么不能用could啊? -How long _____you _____the library book?-For three days. how long have you ___the book ____the library? How long-this library-? How long —l keep the book. how long may I --- the book? How long can the book be （）? How long can I borrow the book? how long may l( )the book? How long------you------(get)the books from the library