泵都工作的情况下，为何中央油箱的油先用（）。
A.中央泵出口粗且多
B.中央泵出口压力大于主油箱的泵
C.中央泵用的电压高
D.中央泵的位置多
参考答案：B
世界上运营里程最长的高铁-京广高铁全线开通，北京至广州全长二千二百九十八千米，写作______千米．
On the double 11th day, my uncle’s online store has successfully sold _____ shoes as last year, that is, it can hardly make ______ progress.
A．as many twice; worse
B．as many twice; bad
C．twice as many; good
D．twice as many; better
