—Why did you plant so many trees? — ______ the environment.
----Could I borrow your camera? ----______, but please give it back by Saturday.
-----May I play computer games now? ------No,_____ you have finished your homework.
----Why do you eat so little? -----I’m afraid I have to be on a diet. I have_____ a lot.
-----Do you know if Miss wang ______ back tomorrow? -----If she ______ back, I will call you.
----What do you think of this book? -----I am _____ in this _____ story book.