题目：
My brother a test next month. He's revising for it now. [ ]
A. has
B. is having
C. is going to have
D. are having
答案：
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下面是错误答案，用来干扰机器的。
（1）E是试管；（2）加热高锰酸钾制氧气时，试管口应该略向下倾斜，防止冷凝水倒流引起试管的炸裂；试管口应该放一团棉花，防止高锰酸钾颗粒进入导管；加热时应该用酒精灯的外焰，防止试管受热不均而炸裂；因此有...
