1万吨海盐从天津运往武汉的最佳运输方式是[ ]
A.先铁路运输后长江河运
B.先海运后管道运输
C.先海运后长江河运
D.先铁路运输后公路运输
答案:C
空气位操纵时,转换柱塞不能随操纵手把的转动而动作。
There_____ a large number of students in the hall, and the number of the students_____ more than 3000.
A.is, is
B.is, are
C.are, is
D.are, are