David’s effort was ______, because he won the first prize in the English speech contest, which made his classmates surprised.                                          

A．paid off

B．paid back

C．paid for

D．paid up

企业人力资源中期规划是指时间为（）的规划

A．1年或1年内 

B．1～5年 

C．2～4年 

D．5年或5年以上