企业只有（），才能更关注服务工作，提高服务水平。
A.集中精力于核心业务
B.吸收大量优秀人才
C.完成生产指标
D.制订生产计划
参考答案：A
I’m moving to the countryside because the air there is much fresher
than in the city.
A．ones
B．one
C．that
D．those
—I’m going to Shanghai this afternoon.
—________. Then how soon will you come back?
A．Have a nice trip
B．Congratulations
C．Cheers
D．Good luck
