男：人生什么最温暖?是寒冬的炉火吗?不是。

女：人生什么最动情?是悦耳的歌声吗?不是。

（男、女）合：是友情，是纯真的友情，是热烈的友情，它能融化冰雪，它能阻挡烈日。现在，我们班的主题班会正式开始。

    某中学七年级(2)班举行以“共享花季友情”为主题的班会，如果你是该班的一员，请参与并帮助解决下列问题。

下列命题：①对角线相等的菱形是正方形；②对角线相等且互相垂直平分的四边形是正方形；③一组邻边相等且对角线相等的平行四边形是正方形；④四边都相等，四角都相等的四边形是正方形.其中命题正确的有（）

“皇帝倒了，辫子剪了，这是1912年给中国人最大的感受。”这直接说明了辛亥革命(　　)

    According to a new Ministry of Education (教育部) survey, student safety has become a big problem. Nearly 50 percent of students say they are worried about robbery on the way to and from school. Now in many big cities in China, some school has taught an unusual lesson: self– protection. Students like this lesson as there are no exams or boring classes. And they can learn how to save lives and know how to stop danger before it really happens.
    Chen Haoyu, a teacher at Beijing No.25 Middle School and a self–protection expert, gives young students advice on how to deal with danger.
    If you are robbed
    Keep calm. If you cannot cry for help or run away, give the robber your money. Try to remember what the robber looks like and tell the police.
    If you are in a traffic accident
    If you are hurt by a car, take down the car number; if it is a bicycle, try to contact your parents before you let the rider go. This is because you don't know how seriously you are hurt.
    If it is raining hard and there is lightning
    Don't stay in high places and keep away from trees.
    When there is a fire
    Get away as fast as you can. Put wet things on your body and try and find an exit. Do not take the lift!
    If someone is drowning(溺水)
    If you can't swim, don't get into the water. Cry out for help.
    Remember that danger is never as far away as you think. Take care of yourself at all times!