题干

从 C+O2 CO2中获得以下信息:①该反应反应物是碳和氧气;②反应发生条件是点燃;③反应前后元素种类和原子个数不变;④反应前后物质种类保持不变;⑤参加反应的碳和氧气的质量比为1:1。其中正确的信息是(   )

A:①②④⑤

B:①②③

C:④⑤

D:①②③⑤

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B

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D

    He Jiang, a postgraduate(研究生)in biology. will become the first Chinese student to give a speech in the commencement(毕业典礼)at Harvard University on May 26, 2016.

    Given the highest honor by the university, He Jiang, who was born in a small village in Hunan province, said, "People in China often believe that it's useless to study and children from the countryside cannot be successful in the future. However, I cannot agree with them. Education can change a person's life. I hope my experience can encourage the students from the countryside to spare no effort in study and make their dreams come true."

    Different from many other families in the village, his parents never thought about finding a job in big cities and leaving their two sons at home without their care. His father was strict about their studies. He and his younger brother studied at home while the other kids in the village played in the fields. Unlike his strict father, his mother took her sons' side when her husband scolded the boys. She preferred to sit with her sons when they studied rather than chat with other women in the village.

    Getting the chance to speak at the commencement is no accident. During his first days in Harvard, it was quite difficult for him to follow the professors in class and he was speechless in campus because of his poor English. Instead of giving up, He Jiang spent all his free time on English. He also made friends with natives to improve his speaking English. One year later, he had little difficulty in class and soon became one of the top students in his class. With the encouragement from Professor Diana Eck. He Jiang decided to apply(申请)for the chance to speak at the commencement.“Few Chinese students had applied before, but I wanted to have a try. I just want to realize my idea of letting more people hear the voice from China and telling them that China is not what it used to be." said He Jiang. After beating three students from Harvard Kennedy School in the third and final round, He Jiang made it to get the chance to speak at the commencement.

    He Jiang will go to Massachusetts Institute of Technology after graduating from Harvard.

同类题4

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        突然,客人惊奇地屏住了呼吸,只见面前的小个子那对浓似灌木丛的眉毛下面,一对灰色的眼睛射出一道黑豹似的目光,虽然每个见过托尔斯泰的人都谈过这种犀利目光,但再好的图片都没法加以反映。这道目光就像一把锃亮的钢刀刺了过来,又稳又准,击中要害。令你无法动弹,无法躲避。仿佛被催眠术控制住了,你只好乖乖地忍受这种目光的探寻,任何掩饰都抵挡不住。它像枪弹穿透了伪装的甲胄,它像金刚刀切开了玻璃。在这种入木三分的审视之下,谁都没法遮遮掩掩。——对此,屠格涅夫和高尔基等上百个人都作过无可置疑的描述。
        这种穿透心灵的审视仅仅持续了一秒钟,接着便刀剑入鞘,代之以柔和的目光与和蔼的笑容。虽然嘴角紧闭,没有变化,但那对眼睛却能满含粲然笑意,犹如神奇的星光。而在优美动人的音乐影响下,它们可以像村妇那样热泪涟涟。精神上感到满足自在时,它们可以闪闪发光,转眼又因忧郁而黯然失色,罩上阴云,顿生凄凉,显得麻木不仁,神秘莫测。它们可以变得冷酷锐利,可以像手术刀、像X射线那样揭开隐藏的秘密,不一会儿意趣盎然地涌出好奇的神色。这是出现在人类面部最富感情的一对眼睛,可以抒发各种各样的感情。高尔基对它们恰如其分的描述,说出了我们的心里话:“托尔斯泰这对眼睛里有一百只眼珠。”