河南成教 / 大学英语Ⅱ
正确率：100%
3[单选题]
atahe _ _ _ speeds which may be zirplanes inthe future ar unpredictable
A.ultimate
B.unsuitable
C.unlikely
D.unknown
atahe _ _ _ speeds which may be zirplanes inthe future ar unpredictable
参考答案：