汽轮机轴承润滑油进油温度应控制在()以内,最高不超过()。
A.40-45℃,48℃;
B.35-40℃,45℃;
C.45-48℃,50℃;
D.40-50℃,52℃。
参考答案:A
Mary _____ to school last week because she _____ill. [ ]
A. didn't go, was
B. didn't went, was
C. doesn't go, is
D. not went, was
飞行环境包括()和空间飞行环。飞行环境对飞行器的结构、()、机载设备和()都有着非常重要的影响。