翻译 How long can I keep the instrument?

翻译 How long can I keep the instrument? how long can I keep the ruler?（选答句） Could you tell me how long I can keep the book.为什么用I can Could you tell me how long I can keep the book? How long can I keep the library book?为什么不能用could啊? How long can I keep this book?是什么意思 英语翻译How long can I keep ……? How long can he keep/keeps the book? How long _______ the book _________(can keep)? How long can I borrow the book? How long may i keep the book 什么意思 how long can I ___ the book?A lend B borrow C get D keep 为何选