It's___last week that the haze in Beijing caused many problem
问题描述：
It's___last week that the haze in Beijing caused many problem
A,reports B.reported C is reported D was reported
不太清楚……
答
不会吧,正确的是B
It' s reported据报道……
因为原句已有动词BE,排除A C 与D
哦抱歉打错了……原句是It___last week that the haze in Beijing caused many problemslast week上周，一般过去时，故正确的是D