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“化学反应条件的控制是实验灵魂”.某校化学兴趣小组在老师指导下,进行了“影响双氧水分解因素”的实验.请你帮助回答下列问题.
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同类题4

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父与女

    ①为翻寻一件秋衣,无意中又在箱底看到了那条围巾,那是用黑色绒绳结成的,编织着宽宽的条纹……在这素朴的毛织物里,编织着我终生难忘的故事。

    ②是十多年前了,一个风雪漫天的日子,父亲自故乡赶来校中看我。

    ③他着了件灰绸的皮袍。衰老的目光,自玳瑁边的镜片后滤过,直似秋暮夕阳,那般温爱、柔和,却充满了感伤意味……他一手提了个衣包,另一只手中呢,是一只白木制的点心盒,上面糊了土红的贴纸,一望便知是家乡的出品。

    ④父亲微微佝偻着身子,频频拂拭着衣领、肩头残留的雪花说:“自从古城沦陷,不知情形如何,我知你母亲时刻记挂着你,只是火车一直不通……我真埋怨自己,当年只埋头读些老古书,自行车都不会骑。不然,阿筠,爸爸会骑自行车来看你的啊……”

    ⑤外面仍然飘着雪,将窗外松柏,都渐渐砌成一座银色的方尖塔,那细弱树枝,似又不胜负荷,时有大团的积雪,飞落下空阶……随了那苍老的声韵,我的眼前出现了一幅图画——一个老人,佝偻着背脊,艰难而吃力地,在凝冻了的雪地上,一步一滑地踏着一辆残旧的自行车……六十二岁的父亲,竟想踏自行车走六百里的路来看我……

    ⑥父亲自衣包中取出我最爱读的《饮冰室文集》,同母亲为我手缝的花条绒衬衣,他转身又解开那点心盒上的细绳,里面是故乡的名产——蜂糕。

    ⑦“你母亲说,这是你小时候最喜欢吃的东西……”他拿起一块,放在我的面前,又摆到我的手上。呵,那被烟蒂熏染得微黄的衰老的手指,此刻还似在我的眼前晃动……当时,也许是我的虚荣造成了我的腼腆吧,在那衣着入时、举止潇洒的两个男女同学注视下,对着这故乡土物,好像有什么鲠在喉头,竟无法吞咽,只窘迫得涨红了脸。

    ⑧天色渐渐地昏暗了,我终于拾起那只“原封没动”的点心盒,只和父亲说了一句:“我拿回宿舍慢慢地留着吃吧。”

    ⑨翌日天色微明,我便匆忙地整理好书包,预备赶回学校去听头一堂的文学史,父亲好似仍觉得我是个稚龄的学童,一手摸着花白胡须:“阿筠,我送你去搭电车!”

    ⑩北国的冬晨,天上犹浮着一层阴云,雪花仍然在疏落地飘着……一路电车终于叮咚地驶来,我才预备跳上车去,父亲又似想起了什么:“你不冷吗?”说着,那么匆遽地,自他的颈际一圈圈地解开那长长的黑色围巾,尽管我在旁边急迫地顿足:“爸,车要开了。”他又颤抖着那双老手,匆遽地把那围巾一圈圈地,紧紧地,缠在我的颈际。

    ⑪我记得那天我着了一件深棕色的呢大衣,镶着柔黄的皮领,那皮毛颜色,直似三月的阳光,又美丽又温暖。但是,父亲却在那衣领外面,仍为我缠起那厚重的毛围巾,直把我装扮成南极探险的英雄了。我暂时忍耐着跳上了电车,赶紧找到一个座位就开始解去那沉甸甸的围巾……一抬头,车窗外,仍然瑟瑟地站着那个头发斑白的老人,依旧在向我凝望,雪花片片地飞上了那光秃的头顶,同那解去围巾的颈际……我的手指,感到一阵沁凉,立时麻痹般不能动转了,只任那松懈了一半的围巾,长长地拖在我的背上……

    ⑫那黑毛绳的围巾,如今仍珍贵地存放在我的箱底,颜色依然那么乌黑光泽,只是父亲的墓地,却已绿了几回青草,飞了几次雪花……

    ⑬抚摸着那柔软的围中我似乎听到一声衰老而悠长的叹息!

(选自张秀亚《种花记》,有删减)

同类题5

根据短文内容,从短文后的选项中选出能填入空白处的最佳选项,并在答题卡上将该项涂黑。选项中有两项为多余选项。

    All around the world, people are working hard to make their cities safer and more pleasant for pedestrians (行人). Cities havepainted crosswalks on their streets, made streets narrower, put in traffic lights and speed bumps (减速带) and madeplans to help more kids walk or bike to school.

    Many people have learned from a man from Brisbane, Australia,named David Engwicht. His book Reclaiming Our Cities and Towns has a simplemessage____. Kids playedthere, and neighbors stopped there to talk.

    But now, streets are just for cars and trucks. People stay inside to get away from the noise and dangerous traffic, and we lose contact with our neighbors____.  People needto take back their streets. Engwicht travels around the world, helping people think differently about pedestrians, streets, and neighborhoods.____. He has workedin neighborhoods from Honolulu to Scotland.

    While Engwicht was writing his book, he learned how neighbors in the city of Delft, in the Netherlands, stopped dangerous traffic on their street. They put old couches, tables, and planters in the street.____. When the police arrived, they saw how these illegal actions made the streets safer. Soon city officials started planning ways to make cars slow down, and“calm”thetraffic.

    Engwicht says we should think about streets as our “outdoor living room”.____

    In the future, streets will be safe places for children again,and our neighbors will become our friends.

a. Cars and pedestrians crowded the street.

b. Calming the traffic is just the beginning.

c. Cars could still pass, but they had to drive slowly.

d. He says that in the past, streets belonged to everybody.

e. It's hard to take measures to solve the traffic problems.

f. Besides his books and articles, he gives many speeches.

g..  Engwicht says that we should use streets for more than just transportation.