干粉手提式灭火器灭火时，先拔去保险销，一只手握住喷嘴，另一只手提起提环（或提把），跑至火场，将喷嘴对准火焰根部
参考答案：对
试论魏孝文帝改革的内容及其意义。
Microblogs experienced rapid growth in 2011 in China, with the number of microblog Operators, users
and visitors ________ several times.
A. to increase
B. increased
C. increasing
D. increase
