TheDongying-Hainanairline        forabout5months.Ihave...

问题详情：

 The Dongying-Hainan airline         for about 5 months. I have taken the flights three times. 

A. is open  B. has opened   C. has been open D. has been opened

【回答】

C

知识点：动词时态

题型：选择题