China is a developing country, ________we all know.

● Maintenance activities include（74）.

①making enhancements to software products

②developing a new software product

③correcting problems

④adapting products to new environments

（74）

A．①②

B．①③④

C．②③④

D．①②③④

A.CHINA TELECOM

B.CHINA LINK

C.CHINA MOBILE

D.CHINA UNICOM

The poverty lines in America and China are the same.()

A.a time-honored brand of China

B.an old and famous brand of China

C.a top brand of China

D.a long-standing brand of China

A.XIAMEN AIRLINES

B.CHINA SOUTHEN AIRLINES

C.CHINA EASTERN AIRLINES

D.AIR CHINA

A.Air China

B.China Eastern

C.China Southern

D.Hainan Airlines