下列关于下图所示装置的说法中，正确的是

A．铜片是该装置的负极

B．负极反应为Zn－2e^－＝ Zn^2＋

C．该装置能将电能转化为化学能

D．装置中电流计指针发生偏转，电子由铜片通过导线流向锌片

用所给单词的适当形式填空。

1. Have you ______ (do) anything to keep the water clean?

2. Project Hope has built schools and ______ (library).

3. Our city ______ (change) a lot since 2001.?

4. The girl left the classroom without ______ (say) anything?

5. All of us want to know how ______ (play) computer games.