质点仅在恒力F的作用下，由O点运动到A点的轨迹如图所示，在A点时速度的方向与x轴平行，则恒力F的方向可能沿（   ）

    What do you think of robots? Will they work for humans in the future?  Maybe we can't answer it.But robots have 1 an important part in our daily life for several years .But in some science fiction movies, the robots are just like humans. Now they help humans with the housework and do the most 2 jobs.

    Many scientists believe that there will be such robots in the future.3they agree it may 4 hundreds of years. Scientists are now trying to make robots look like people and do the same things as us.

    But robot scientist James White 5 He thinks that it will be 6 for a robot to do the same things as a person7 it's easy for a child to wake up and know where they are. Mr. White thinks that robots won't be able to do this. But other scientists disagree. They think that robots will be able to talk to people 8 25 to 50 years.

    Robot scientists are not just trying to make robots look like people. For example, there are already robots working in factories. They do many 9 over and over again. People would not like to do such jobs and would get bored. But robots will10 get bored.

    In the future, there will be more robots everywhere, and humans will have 11 work to do. New robots will have many different12. Some will look like humans, and13 might look like snakes. After an earthquake , a snake robot could help look for people under buildings. That may not seem possible now, but computers, space rockets and even electric toothbrushes 14 impossible a hundred years ago. With the 15of science technology. We never know what will happen in the future! Let's work much harder to make robots serve us better!

资料卡片：氨气通常情况下是有刺激性气味的无色气体，密度比空气小，能使湿润的红色石蕊试纸变蓝色，极易溶于水．实验室常用加热熟石灰和氯化铵固体混合物制取氨气，若要快速产生氨气，可以将浓氨水滴加到生石灰中得到．请根据有关信息回答下列问题：

鼓神

王雁

    ①那一年冬天，我流落到陕西省略阳县。这里地处秦岭腹地，山高坡陡民穷，是李白为之嗟吁的蜀道第一关。因为生意亏了本，我流连在这里，贩点山货倒点野味，甚是凄惶可怜，甚至到了春节年关还不敢作归乡的打算。

    ②春节的气氛越来越浓，鞭炮声鼓锣声从街巷小院传来，听得人心烦意乱，无奈中，我裹掖着衣服离开县城走向一个熟悉的小山村。谁知这里也在操练鼓锣作春节上街游行的准备。既然躲不掉就留下来听听吧。于是我就混在一帮老头婆姨姑娘小孩子中间看着坝中十来个中青年汉子把鼓锣敲得震天价响。

    ③敲打锣鼓的汉子们敦实威风，这些平时在山中辛苦刨食的人此时一个个精神抖擞，红光满面，卖着狂傲，逞着威风，显得不可一世。这气氛使我这个异乡人感到更加的凄惶悲哀，孤独孑孑。我准备悄悄地离开。正在这时，敲打大鼓的壮汉把双槌一收，抹一下额上的汗水，用眼光把人群扫了一遍，最后目光定在我身边的一个瘦老头身上，说：“张伯，你来玩一把。”“别，别……”，这个叫张伯的老头既瘦弱又邋遢，穿着一件破旧的黑布棉袄，双手操在袖筒中甚是羞惑地直往后退。我感到他也是像我一样的怕过年的落魄人。但姑娘媳妇们却揪住他往前推搡，说：“鼓神，来一个！”打鼓的汉子一脸虔诚，把有如婴儿手臂粗的双槌直往他面前送，那些打小鼓腰鼓铜锣铜钹的后生们也满脸殷殷地望着他……这倒引起了我的好奇。

    ④可能感到再也推辞不了，张伯突然像运气似的抡了抡手臂，脱袄，仍衣，大步流星，就站稳在了大鼓前。他拉开架势，将双槌高擎过头，布满皱纹和胡茬的脸上突然焕发豪气万丈，一个在黄土中长大的像黄土一般普通的汉子忽然间像天神降临高耸在鼓阵中间；一个在群山中滚爬像山石一样平凡的山民一瞬间如金刚发威挺立在群峰之上。．他的眼睛充满光辉，脸上透出神圣，在轻敲几下鼓沿后，双臂猛一挥，一声石破天惊的巨响倏地刺进了我的耳膜和心脏，接着小鼓铜锣一起轰鸣，一股原始混沌的神秘冲动和古老意念的混乱音符猛地从地底蹿出来通过双脚直抵进了我的心中，使我有了一种脱胎换骨般的剧痛的快感。

    ⑤我像被魔语诅咒了似的，双目紧盯着他，只见他急敲慢叩--急如狂风暴雨，缓似岚岗生月；重擂轻掠——重如万马奔腾，轻似惊鹿踏雪，把一面鼓指派得出神入化。除了力的迸射，还有技的绽放。老人时而槌抹鼓沿，时而肘杵鼓面，时而跃腾猛捶，时而低伏轻抚，柔时如丝绸无骨，刚时像枪挑滑轮；乱则乌云横飞，齐则兵阵突进。铁马兵戈飞鸣镝，细雨轻风荷叶清，劈山开路是男儿，再闻堂前机杼声……

    ⑥轰鸣！呼啸！冲突！纠缠！齐整！狂乱！

    ⑦就在敲击出的声声鼓鸣中，我似乎听到了天庭的意志，大地的精神，男人的cū guǎng _____，女人的娇娉，还有生命，婴儿落地开始的生命，老人撒手西去的生命……这些奇妙的幻象在锣鼓声交织而成的音韵的罗网中不断地冲突，纠缠，呼啸，狂乱……它们似在演绎着生命，似在点拨着生命，似在操纵着人类奔向精神将要达及的终点……

    ⑧我虽然肃立的山民之间，我虽然肃立在山民中间，但精神却是跪着的。形似卑微而神不卑微，处身卑微而心不卑微——调度这阵势，创造这奇迹的老者已不再是一个焉耷汉，而是一个飘逸的精灵！这个人中的英杰此时就代表着人类在立地顶天！我惊愕了，世上竟有着这样的声音，这是一串神秘的符号，一团无形的罡声；我醒悟了，生命中原本就没有卑微和可怜，卑贱者豪迈，低微者挺拔，全在于自己．

    ⑨我从人群中慢慢地退了出来，充满敬意地望着他们。我想我该回家过年了。