读俄罗斯、印度图，回答下题。

“垃圾是放错了地方的资源”，应分类回收利用．生活中废弃的铁锅、铝制易拉罐、铜导线、废旧电池的锌皮等属于（　　）

   Last week, 169 students at No.35 Middle School of Shenyang took their first no-teacher exam. After the teacher handed out the exam paper, he left the room and never came back. A student collected in the papers when the exam ended.
   “That test was not only a test of knowledge, but also a test of moral (道德). We wanted to show students how important honesty is, ” said Mr. Cai, the school's headmaster. The school says no cheating happened in the test. Next year, it wants 80% of its exams to be without teachers. But students have different ideas.
   “I was happy and excited during the exam because my teachers trusted me,"said Lang Yudan, a 13-year-old girl in Class 11.
   “Schools must trust students a lot not to use invigilators(监考人). But I think it is too early. Some students will cheat if there are no invigilators. And the students will not be able to ask for help when needed,” said Hua Sha.
   “I don't like having invigilators in exams. When they walk around the classroom, they make me nervous. I would get higher marks without them in the room because I would feel more relaxed," Liu Qingxi said.
   “I think it's very important to have invigilators in exams. Many students want to check their answers with each other after they have finished papers. And they can also keep the classroom in order when something unusual happens. They may make me nervous, but I still think we need them," Shangguan Yan said.
   Not using invigilators may be a good idea. But before using it, schools must tell students the importance of honesty and try to find ways to solve something unusual in exams.

B

    I'm David. Long ago I came to the city near my hometown to find a job. I met all kinds of difficulties and I used up all my money soon.

    It was dark outside one day. I got on a bus quietly. Suddenly, a passenger cried in a loud voice, "someone has stolen my money!" I felt nervous, because his money was in my hand. Some people suggested the driver drive the bus to the police station, but some were against it because they were in a hurry to go back home. The whole bus was very noisy. The driver then stopped the bus by the roadside and turned on the lights. At that time, one passenger said, "Turn off the lights and give the thief(小简)a chance to take out the money."Then the bus got dark.

    When I was still thinking about whether to take out the money or not, the lights were turned on again. There was no money on the floor. Someone said, "Give him one more chance." Then the lights were turned off again. I became even more nervous. The lights were turned on again but they got the same result.

    Then the passengers fell into an open discussion. Later, someone said, "Give him the last chance!" I felt awakened(醒悟的) and took out all the money when the lights were turned off again.

    For many years I have been grateful to those who gave me three chances. When the first and Second chances come, you may not be prepared well or don't have enough courage to act. When the third chance comes, you should know clearly what you should do.

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