问：It was two decades ago ---- I was in my teens------- the Chinese goverment decided to reform the social economic system
It was two decades ago 选项： A when when B that which C when that D before that
答：C
析： I was in my teens 是补充20年前,当我还是个少年的时候, IT WAS two decades ago THAT the Chinese goverment decided to reform the social economic system .这里的 it was……that……是强调句型