题干

2016 年4 月13 日21 时55 分在缅甸发生7.2 级大地震,造成很大的人员和财产损失.下列有关地震涉及的物理知识说法中正确的是(   )

A:地震时,山上的石块在下落过程中重力势能减小,动能增大,机械能增大

B:救灾的直升飞机保持一定高度水平匀速飞行并空投物资过程中,飞机机械能不变

C:直升飞机加速升空时,因螺旋桨转动在桨上下表面形成压强差使其所受升力等于重力

D:由于惯性,救援人员必须提前在飞机还未到达目标区域上方时投放物资

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D

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    Can you write the Chinese characters “ganga” (embarrassment) correctly? Do you know how to write characters like “tiaozhou” (broom)?

    If you can’t, you’re not alone. Nowadays, most people are typing into computers instead of writing on paper. We type Chinese characters largely according to their pronunciations. The result is to recognize characters without remembering how to write them.

China Youth Daily once did a survey among about 2,500 people, in which about 99 percent said they had once forgotten how to write a common Chinese character.

    Compared to adults, teenagers are better at writing Chinese characters because they spend more time learning and practising at school. However, the influence of digital technology cannot be ignored (忽视),according to He Yu, head of a research team for Chinese teaching at a Beijing high school.

    “Many students are obsessed (沉迷于) with digital devices such as electronic dictionaries and computers to help with their studies. Overuse of these tools will make students too lazy to think and write,” he said.

    Such worries have brought about a popular TV show titled Chinese Spelling Hero, which focuses on Chinese character writing among teenagers. In April, the Ministry of Education called for a better calligraphy (书法) education in schools. Organizations like the China Calligraphers Association are also working to train more teachers in calligraphy.

    Interestingly, calligraphy teachers can’t always avoid the effects of modem technology. Shen Bin is a calligraphy teacher at a primary school in Beijing. She admitted that it’s common for teachers like her to forget certain words.

    “The calligraphy class is also a good chance for me to remember how to write,” she said.