If you are tired, you can ________ a rest.
---When can we use this lift? ---Not until it____________ next week.
________ students in the classroom ______ twenty. The others are in the library.
— Do you believe that paper is made _______ wood? —Yes, I do. And you can see that books are made________ paper.
______ is said that our math teacher often does volunteer work on weekends.
I took the wrong train _______. I didn’t even know it until half an hour later .