Question

—__________ do I have to change the robot’s batteries? —Every two months.

A．How long

B．How soon

C．How often

D．How many

Answer 1

C

本题的回答语意思为每两个月，表示的是频率，对此提问应该用how often，故选C,how long对长度提问，how soon对多久以后提问，how many对可数名词数量提问。