单项选择。
What time is it now?[ ]
A. It's time for PE class.
B. It's nine o'clock.
答案:B
There are _____________ months in a year. [ ]
A. twelve
B. twenty-four
C. sixty
对于从国外进口的变压器油进行验收时,应参考()。
A.国家标准
B.国家标准(ISO)标准
C.生产国标准
D.国际电工委员会(IEC.296标准