Recently, the serious problem of smog caused by PM2.5______greatly by the govern

游客2023-09-20 16

问题 Recently, the serious problem of smog caused by PM2.5______greatly by the government’s effective measures.

选项 A、improved
B、had improved
C、has been improved
D、has improved

答案 C

解析本题考查句子时态。句首的Recently一词提示，本题应使用现在完成时态；分析句子成分可知，主语是the seriousproblem，主语和谓语动词improve存在被动关系，故空格处所填动词应为第三人称单数形式，且使用被动语态。所以，C)为本题的正确答案。

转载请注明原文地址:https://www.tihaiku.com/zcyy/3031463.html

相关试题推荐

随机试题

最新回复(0)

What’stheproblemtheworldisnowfacing?Theworldisnotonlyhungrybutit