It’s an________.
I spent three hours_____ this book.A. finish readingB. to finish readingC. finishing reading
——What are you doing _______ vacation?A. to B. for C. at
You have a ___ . You should stop eating anything.A. headache B. Backache C. stomachache
——______ do you go camping?——Once a month.A. How long B. How often. C. How many.
We should eat ____ food and it is good for our ____.A. healthy; healthB. health; healthC. healthy; healthy