从某种角度而言，世博会的举办，对（）的积极影响是最为直接。
A.商业
B.交通运输业
C.旅游业
参考答案：C
A big party was held in NO.18 Middle School last night, the teacher with students _____ singing and
dancing happily at the party. [ ]
A. is
B. was
C. are
D. were
His aunt’s letters him of those beautiful days when they used to live together in his hometown.
A．call up
B．call for
C．call on
D．call at
