There is a new problem involved in the popularity of private carsroad conditions need.A. t

There is a new problem involved in the popularity of private cars road conditions need .
A. that；to be improved
B. which；to be improved
C. where；improving
D. when；improving

(答案→)A. that；to be improved B. which；to be improvedC. where；improvingD. when；improving解析：考查同位语从句和固定词组。Need doing=need to be done需要做某事；同位语从句conditions need .解释名词a new problem

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