21 They broke into prison and set free all the people in prison.
A. the ,/ B. /,/ C. the ,the D. /,the
22 By comparing prices and offers, you can also make your travel last longer.
A. salary B. budget C. income D. conditions
23 Can you think of some cases drivers obviously knew the traffic rules but didn't obey them?
A. why B. where C. as D. which
24 just south of Yunnan and Guangxi, Vietnam is easy reach and offers exciting adventures at a reasonable price.
A. Locating; within B. Located; in
C. Located; within D. Locating; in
