I ______ go to bed until I ______ finished my work.
Can you see that building ______ by trees? That’s ______ we study.
Sir, you ________ take this seat. It’s just for the old.
______ life began on earth is one of the biggest puzzles that scientist found hard ______.
Was it because his mother was ill ______ he didn’t go to school?
What ______ will it ______ whether you are a boy or a girl ? As long as you set your mind to it, nothing can be difficult.