题干
— How nice the fish tastes! Could you tell me who taught you to cook it?
— I learnt it _______watching TV. I learn to cook many dishes_______ TV.
A：by; in
B：by; on
C：in; on
D：in; in
答案(点此获取答案解析）
B
合成它用了三种单体，这三种单体的结构简式分别是 