Last week, our class was    duty in the cafeteria for student self-management. On the first day, I   (shock) to see so much leftover food thrown away by students. What a waste! Being concerned about it, my classmates and I had a   (heat) discussion on how   (solve) the problem. Lots of good ideas came up, such as holding class meetings, putting up wall newspapers and charging a fine for wasting food. Finally, we all agreed that wall newspaper would be    (good) choice.
The next day, we put our idea into reality. Towards lunch time, we put up a wall newspaper outside the school cafeteria,     (call) on students not to waste food. Many students gathered around to read and    (express) their support. To my great delight, there were changes soon. In the cafeteria, I found the trays returned after lunch all empty    any leftover. Food  (save) and the dining hall was cleaner. Seeing this, I felt relieved and proud of   we had done.