空调出风口最少（）（时间）彻底查使一次。

用括号里所给词的正确形式填空。

1. The problem is too difficult. It took me half an hour ____________ ( work ) it out.

2. Most people like easy jobs and don't like to do the __________ (pleasant)work.

3.There are some patients _________( wait ) for the doctor.   

4. When I walked past,I saw him __________ (play) computer games.  

5. Hurry up, the train _______________(leave) in two hours。

出口货物退（免）税应当由（）以上税务机关根据审核结果按照有关规定进行审批。

A．县级

B．设区的市、自治州

C．省级

D．国家税务总局

血液循环的动力器官是______．血液循环包括______循环和______循环．

固定花材的用具

提出“学习风格”概念的学者是( )。

A．奥苏伯尔
B．加涅
C．布鲁纳
D．塞伦