某商店将成本为30元的文化衫标价50元出售．

    According to a recent survey,violence did exist in schools. Students ____ (show) their fear and parents and teachers also expressed their great concern about it. ____ (expert) hope the whole society will pay more attention to the mental health of adolescents.

    Nowadays, school violence is ____ hot issue. I think this is a phenomenon（现象）, ____ calls for our great concern.We should try every effort ____ (prevent) violence happening at school for more and more students would drop out of school if their personal ____ (safe) could not be guaranteed.In fact,violence can be learned.Children learn violent behavior from adults or from ____ they see on television or on the Internet.

    If I meet with school violence,I will not answer violence ____ violence, for it will result in ____ (much、fighting.I will tell my teachers or parents about it.I think they will help me deal with it well and they will protect me from the bad guys.

    All in all, every student should behave ____ (he) and keep away from violence.

刺激某一个神经元引起后一个神经元兴奋。当给予某种药物后，再刺激同一个神经元，发现神经冲动的传递被阻断，但检测到突触间隙中神经递质的量与给予药物之前相同。这是由于该药物（   ）

1896年，沙俄诱使中国政府与之签订《中俄密约》，迫使中国政府同意，让俄国的远东铁路从满洲里进入中国境内，再从绥芬河入俄境。这段在中国境内的铁路干线称中东路……沙俄政府被推翻后，美国为阻止日本乘机独享中东路利权，与法、英、日、意及中国联合共管远东铁路，包括中国境内的中东部。

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