—Our country ______ a lot so far.

—Yes. I hope it will be even ______.[ ]

A. has changed; well      

B. changed; good

C. has changed; better    

D. changed; better

第三蠕动波见于（）.

A.食管静脉曲张

B.食管癌

C.老年人及食管贲门失弛缓症患者

D.食管憩室

E.以上都不是