润滑油冷却器的作用：是（）。
参考答案：冷却润滑油，降低轴承温度
However, in ______ recent years, _________ Niagara Falls have come to be appreciated more for
their natural beauty as _________ wonder of Nature.
A. /; the; a
B. the; /; the
C. /; the; /
D. the; /; a
治疗肺胃出血，宜首选（）
A．白及
B．大蓟
C．槐花
D．地榆
E．白及根
