闭斗中有什么要求?
参考答案:
开斗中制动一个工作刹车,另一个松闸,作用使斗不坠落。闭斗中两个制动器均松闸作用抓斗抓的满一点利用抓斗自重在抓过程中逐步下沉。
Though _____ to see us, the professor gave us a warm welcome. [ ]
A. surprising
B. was surprised
C. surprised
D. being surprised
脱式计算,能简便的就简便运算.
4.6+5.4×6
4.9×0.46+4.9×0.54
32-2.3×6
(0.4+4)×2.5
25-7.8-2.2
1.25×2.5×0.8×4.