A：电极一定要由两种不同的金属组成
B：电子流出的一极是正极
C：两极均发生氧化还原反应
D：由化学能转化为电能的装置
— Mr Zhang really has a great sense of __________.
— Yeah. He often makes us laugh.
— Look! There is a monkey eating ________ apple in the tree.
— En, ________ monkey is very cute.
