The air quality in this area has improved a lot since that factory ___. A. was closing B. would close C. closed D. will close

The air quality in this area has improved a lot since that factory ___.

A. was closing 
B. would close
C. closed 
D. will close

Trả lời

Chọn C

Câu hỏi cùng chủ đề

Xem tất cả