一般单级泵的封油压力，和机泵压力相比是（）。
A、低
B、高
C、一样
D、无法确定
参考答案：B
明长城西起____________，东到____________，是世界奇迹之一。
Li Lei isn't ____ Liu Ming. [ ]
A. tall as
B. as taller as
C. as tall as
D. as the taller as
