题目

Communication   Choose the best choice from A to F to finish the dialogue. You have one more answer. Each choice should be used only once. A: Hi, Peter. I see you wearing a pair of glasses. But you didn’t wear it before, did you? B:     (1)     But I’m afraid I have to wear it now. A:     (2)    B: Because I get screen sightedness（近视症）and     (3)    A:     (4)     What happened? B: My doctor said that I watched movies or played games on my iPad quite a lot. I suggest you not to do that like me. A:     (5)      Peter. B: You’rey=cosπ2xcosπ2(x-1)的周期为 ．