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参考答案：
参考解析：
刷刷题刷刷变学霸
举一反三
【单选题】A Long, long ago people made fires from lightening (闪电 ). But they had to keep the fire burning, for they couldn't start it again if there was no lightening. Later, they found out hitting two pieces o...
A.
making a hole in a big piece of wood
B.
putting a smaller stick into the hole
C.
turning the stick hard for a while
D.
doing all the above in order