Have you returned the book to the library ____? —Yes, I have ____ returned it.

Hello, Holiday Hotel. Can I help you?—Do you have a room for this weekend?

China’s first lady ____________the home-made clothes to visit Russia in March,2013.

I hear that Lily’s brother is a worker here.—Look! The manis working over there is her brother.

No matter how ______，scientists are eager to know more about it by exploring.