A few months ago, a strange thing happened in my life. I heard a strange sound outside the window every night. I was scared and didn't know what to do. I thought there might be a thief standing outside the window was closed. I asked my parents to see what it was. But they didn't find anything. They thought it might be the wind. But I didn't think so.

    That lasted for a few days. I couldn't sleep well. Sometimes I even couldn't fall asleep, One day, I bought a flashlight(手电筒) in a market. At midnight, as soon as I heard the strange sound, I jumped out of my bed with the flashlight. I saw a black cat jumping up and down near thewindow. He might want to make friends with my pet cat, but he couldn't get into my house.

    Do you think it is strange? Have you ever had this kind of experience in your life?

⑴--⑷根据短文内容，回答问题⑸英译汉

1929—1933年，资本主义世界发生了一空前严重的经济危机，使美国的经济政策由胡佛的自由放任转变为罗斯福的国家干预。你认为这一变化的实质是（    ）