机泵的密封冲洗油主要是为了使机械密封面得到()。
A、减少摩擦
B、防止腐蚀
C、密封和减振
D、冷却和冲洗
参考答案:D
In the eyes of the Americans perhaps the most laughable thing Daiwa did was to announce that members of its board of directors would accept responsibility for the affair by taking 30% salary cuts for six months.
A.audacious
B.auspicious
C.ridiculous
D.frivolous
优良的天然木材,经刨切或旋切加工方法制成的薄木片是()。
A.木质装饰单板
B.装饰面板
C.大芯板
D.复合板