问题
选择题
对于不重合的两个平面α与β，给定下列条件：
①存在平面γ，使得α，β都平行于γ
②存在平面γ，使得α，β都垂直于γ；
③α内有不共线的三点到β的距离相等；
④存在异面直线l，m，使得l∥α，l∥β，m∥α，m∥β．
其中，可以判定α与β平行的条件有 [ ]
A．1个
B．2个
C．3个
D．4个
答案
答案：B
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对于不重合的两个平面α与β，给定下列条件：
①存在平面γ，使得α，β都平行于γ
②存在平面γ，使得α，β都垂直于γ；
③α内有不共线的三点到β的距离相等；
④存在异面直线l，m，使得l∥α，l∥β，m∥α，m∥β．
其中，可以判定α与β平行的条件有 [ ]
A．1个
B．2个
C．3个
D．4个
答案：B
Mike didn’t do his English homework. The teacher asked him 31 . “I’m sorry, I 32 .” “But why did you forget?” “It didn’t seem 33 or important,” said Mike. “Are you going to punish (惩罚)me?” asked Mike. “ 34 . The punishment is for me. I didn’t teach you well,” said the teacher. “Thank you,” said Mike. “You are the best 35 in the world. I can never know as much as you , but you taught me a lot.” “How can I be a good teacher if the students do not know more than me? I will not succeed until that happens,” 36 the teacher. Mike’s 37 teacher was a strict（严厉的） man.. Every day Mike played the same piece of music,and the teacher said it was not good and he must practise 38 . After two years of hard work, Mike left and felt sad. 39 when he played it in public, everyone said it was perfect, and he found he could play other pieces of music easily. What do you think of these two 40 ?
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