高等继续教育 / 高级英语II
正确率：100%
题型描述: 单选题
＿＿＿＿＿＿ we develop a new kind of car, air pollution will become even more dangerous.
A.In case
B.If
C.Although
D.Unless
＿＿＿＿＿＿ we develop a new kind of car, air pollution will become even more dangerous.
A.In case
B.If
C.Although
D.Unless
参考答案：