选A.
首先problem后面的involved in the popularity of cars做problem的定语,而road conditions···则做problem的同位语.所以可以确定前一个空填that.而need doing sth 就相当于 need to be done.所以后一个的答案都可以.综合前一个空,应该选A.
选A.
首先problem后面的involved in the popularity of cars做problem的定语,而road conditions···则做problem的同位语.所以可以确定前一个空填that.而need doing sth 就相当于 need to be done.所以后一个的答案都可以.综合前一个空,应该选A.