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飘落的广告单

韩研研

    桥头，一个60多岁的老太太捧着一叠产品宣传单，一张张地发给骑自行车或过路的行人。

    老太太的脸上没有任何表情，她木然地望着来往的路人，一只手机械般地摆动着——她已经在那里站了很久、很久了。

     一张广告单塞到一位穿着入时的小伙子手里，小伙子说：“噢，我不需要。”老太太像没听见似的，只顾着发。只见小伙子用手轻轻一弹，那张白纸黑字的广告单便飞起来。

    一个学者模样的中年男子，骑着自行车过来了。老太太照例发给他一张，中年男子没有接到，老太太已经松手了，又一张广告单扔到了地上。

    过了一会儿，一位年轻的母亲带着一个三四岁的孩子骑车过桥。老太太抽出一张广告单想放在车篓里，但手却碰到车龙头上。年轻的母亲“呀”地叫了一声，自行车摇晃了几下，随着一句“讨厌!”一张广告单悠然飞落……

    不远处，一个男清洁工一边扫着地上的广告单，一边哺哺地骂着什么，那飘落的广告单几乎覆盖了桥面。就这样，老太太“扔”完了广告单，拎着空人造革包正要走，一个二十八九岁的小伙子风风火火地来到了老太太的身边：“妈——你怎么呆在这里呀？”老太太闻声绽开了笑脸：“儿呀，我呆在家里闷得慌，不如出来发发广告单，还能挣点钱花呢！”小伙子看着满地的广告单说：“妈，您这不是灯草儿架桥——白搭吗? ”老太大摇着脑袋道：“唉，反正发完了拿钞票。”她儿子点点头说：“这倒也是。不过——”

    忽然，小伙子像想起了什么，从地上捡起一张印满脚印的广告单，他马上愣住了。半晌，儿子才大叫起来：“我的妈呀——这是我承包的工厂，花了几千元给广告公司印发的产品广告单呀。”

下图漫画形象地反映了  (    )

    In colleges around the country, most students are also workers. The reality of college can be pretty different from the images presented in movies and television. Instead of the students who wake up late, party all the time, and study only before exams, many colleges are full of students with pressing schedules of not just classes and activities, but real jobs, too.

    This isn't a temporary phenomenon. The share of working students has been on the rise since the 1970s, and one-fifth of students work year round. About one-quarter of those who work while attending school have both a full-course load and a full-time job. The arrangement can help pay for tuition (学费) and living costs, obviously. And there's value in it beyond the direct cause: such jobs can also be critical for developing important professional and social skills that make it easier to land a job after graduation. With many employers looking for students with already-developed skill sets, on-the-job training while in college can be the best way to ensure a job later on.

    But it's not all upside. Even full-time work may not completely cover the cost of tuition and living expenses. The study notes that if a student worked a full-time job at the federal minimum wage, they would earn just over $15,000 each year, certainly not enough to pay for tuition, room, and board at many colleges without some serious financial aid. That means that though they're sacrificing time away from the classroom, many working students will still graduate with at least some debt. And working full time can reduce the chance that students will graduate at all, by cutting into the time available for studying and attending classes.

    There is little reward for attending but not finishing college. Students who end up leaving school because of difficulty in managing work and class are likely to find themselves stuck in some of the same jobs they might have gotten if they hadn't gone at all. The difficulty of working too much while in school can create a cycle that pushes students further into debt without receiving any of the financial or career benefits.

用相应的化学符号填空：
①2个氟原子____ ； ②3个氮分子____ ；③2个铜离子____ ；④硫酸铁中铁的化合价____ ；⑤人体内含量最多的物质是____；     ⑥常用做白炽灯灯丝的金属____ 。