污水处理站的空间除硫装置有（）台循环泵。
A.15
B.2
C.3
D.4
参考答案：B
It is necessary that we should spend one hour _____ English every morning. [ ]
A. practice to read
B. practice reading
C. practicing reading
D. practicing to read
以下哪些文件系统是Windows2000所支持的（）
A.FAT
B.FAT32
C.HPFS
D.NTFS
