读下列寓言，回答问题。

穿井得一人

      宋之丁氏①，家无井，出汲②，常一人居外。及其家穿井，告人曰：“吾穿井得一人。”有闻而传之者曰：“丁氏穿井得一人。”国人道之，闻之于宋君③。宋君令人问之于丁氏④。丁氏对曰：“得一人之使⑤，非得一人于井中也。”求能之若此，不若无闻也。 

——本文选自《吕氏春秋》书卷二十二《慎行论·察传》

    【注释】：①氏：姓。②汲：音jí，从井里打水。③闻之于宋君：这件事被宋君听到了。之：代词，指“丁氏穿井得一人”一事，是“闻”的宾语。于：介词：当“被”讲，引进主动者。宋君：宋国国君。④问之于丁氏：向丁氏问这件事。于：介词：当“向”讲。⑤使：使用，使唤，指劳动力。于：到，向。

阅读表达 (阅读短文，并根据短文内容回答问题。)

    Computers are useful machines．They can help people a lot in their daily life ． For example，they can help people to save much time to do much work，and they can help people to work out many problems easily．Our country asks everyone to learn to use computers before the twenty-first century，except the old people．

    Today more and more families own computers ． Parents buy computers for their children．They hope computers can help them improve their studies in school．Yet，many of their children use computers to play games，to watch videos or to chat．Computers can not help children to study but make them fall behind．So computers are locked in boxes by parents．

    In some other countries，even some scientists also hate computers．They say computers let millions of people lose their jobs or bring them a lot of trouble．Will computers really bring trouble to people or can they bring people happiness? It will be decided by today's students themselves!

将一根圆木锯成3段要12分，再将每段平分成两份，还要（　　）分钟．

关于二氧化碳与一氧化碳性质说法正确的是（　　）