从根本上讲，元朝能够统一中国并维持近百年的原因是(　　)

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       那店小二那里敢过来，连那正要买肉的主顾也不敢拢来。

       郑屠道：“着人与提辖拿了，送将府里去？”鲁达道：“再要十斤寸金软骨，也要细细地剁做臊子，不要见些肉在上面。”郑屠笑道：“却不是特地来消遗我！”鲁达听得，跳起身来，拿着那两包臊子在手，睁着眼，看着郑屠，道：“酒家特地要消遗你！”把两包臊子劈面打将去，却似下了一阵的“肉雨。”郑屠大怒，两条忿气从脚底下直冲到顶门；心头那一把无明业火焰腾腾的按纳不住；从肉案上抢了一把剔骨尖刀，托地跳将下来。鲁提辖早拔步在当街上。

       众邻舍并十来个火家，那个敢向前来劝；两边过路的人都立住了脚；和那店小二也惊得呆了。

       郑屠右手拿刀，左手便来要揪鲁达；被这鲁提辖就势按住左手，赶将入去，望小腹上只一脚，腾地倒在当街上。 鲁达再入一步，踏住胸脯，提着醋钵儿大小拳头，看着这郑屠道：“酒家始投老种经略相公，做到关西五路廉访使，也不枉了叫做”郑关西！”你是个卖肉的操刀屠户，狗一般的人，也叫做“郑关西！”你如何强骗了金翠莲？”扑的只一拳，正打在鼻子上，打得鲜血迸流，鼻子歪在半边，却便似开了个油铺：咸的，酸的，辣的，一发都滚出来。郑屠挣不起来，那把尖刀也丢在一边，口里只叫：“打得好！”鲁达骂道：“直娘贼！惫敢应口！”提起拳头来就眼眶际眉梢只一拳，打得眼棱缝裂，乌珠迸出，也似开了个彩帛铺的：红的，黑的，紫的，都绽将出来。

       两边看的人惧怕鲁提辖，谁敢向前来劝？

       郑屠当不过，讨饶。鲁达喝道：“咄！你是个破落户！若只和俺硬到底，酒家便饶你了！你如今对俺讨饶，酒家偏不饶你！”又只一拳，太阳上正着，却似做了一全堂水陆的道场：磐儿，钹儿，铙儿，一齐响。鲁达看时，只见郑屠挺在地上，口里只有出的气，没了入的气，个动掸不得。

       鲁提辖假意道：“你这厮诈死，酒家再打！”只见面皮渐渐的变了。鲁达寻思道：“俺只指望打这厮一顿，不想三拳真个打死了他。酒家须吃官司，又没人送饭，不如及早撒开。”拔步便走，回头指着郑屠尸道：“你诈死！酒家和你慢慢理会！”一头骂，一头大踏步去了。

       街坊邻舍并郑屠的火家，谁敢向前来拦他。

       鲁提辖回到下处，急急卷了些衣服盘缠，细软银两；但是旧衣粗重都弃了；提了一条齐眉短棒，奔出南门，一道烟走了。

    I fell in love with Yosemite National Park the first time I saw it, when I was 13. My parents took us there for camping. On the way out, I asked them to wait while I ran up to E1 Capitan, a1 rock of 3,300 feet straight up. I touched that giant rock and knew 2 I wanted to climb it. That has been my life's passion (钟爱) ever since—3 the rocks and mountains of Yosemite. I've long made Yosemite my 4.

    About 15 years ago I started seeing a lot of 5 like toilet paper, beer cans, and empty boxes, around the area. It's6 me why visitors started respecting the place 7 and treated such a beautiful home-like place this way.

    I tried 8 trash (垃圾) myself, but the job was too big. I would9 an hour or two on the job, only to find the area trashed all over again weeks later. Finally, I got so 10 it that I decided something had to change.

    As a rock-climbing guide, I knew 11about organizing any big event. But in 2014, together with some climbers, I set a date for a 12. On that day, more than 300 people 13 Over three days we collected about 6,000 pounds of trash. It was amazing how much we were able to14 I couldn't believe the15we made —the park looked clean!

    Each year volunteers come for the cleanup from everywhere. In 2016 alone, 2,945 people picked up 42,330 pounds of trash and16132 miles of roadway.

    I often hear people17about their surroundings. If you are one of them, I would say the only way to change things is by 18rather than complaining. We need to teach by 19.You can't blame others 20 you start with yourself.

某校化学兴趣小组就空气中氧气的含量进行实验探究：

【收集资料】硫是一种淡黄色固体，在空气中点燃时能与氧气发生反应生成二氧化硫（表达式：S+O₂ $\underset{\_}{\underset{\_}{点燃}}$ SO₂），SO₂是一种有刺激性气味的气体，易溶于水．

【设计实验】第一小组同学选择的药品是足量的红磷，设计如图1．

在“夸父逐日”中，“夸父”是怎样追逐太阳的? （     ）