问题 多项选择题

在一个运行OSPF的自治系统之内:()

A、骨干区域自身也必须连通的

B、非骨干区域自身也必须连通的

C、必须存在一个骨干区域(区域号为0)

D、非骨干区域与骨干区域必须直接相连或逻辑上相连

答案

参考答案:A, C, D

阅读理解

Teaching English to your family members is a great way to improve your own English. Learning something new together can make you closer to your family members, too.

Here is some advice for you:

Film night: choose an English film with Chinese subtitles字幕. You can stop the film at any time and help your family learn new words and expressions according to subtitles on the screen.

Sports night: you can invite your family members to go skating or swimming. You can teach a few words when you play sports together. For example, “you fell down” or “your skates look cool”.

Novel night: choose a classical English story that your family members may know. You can read it to your family members and tell them about the novel in English

Make an English family tree together: you can teach your family members what each person is called in English, such as “father” and “cousin”. It is a good way to make your family members interested in English.

小题1:you can learn English by ___ according to the passage.

A.listen to the radio

B.teaching English to your family members

C.taking to your English teachers

D.having a party and talking in English小题2:you can help your family members___ when you watch an English movie

A.listen to English songs

B.review some sentences

C.copy some conversation

D.learn some words小题3:which of the following is TRUE according to the passage?

A.you can only help your family members learn English at night

B.translating a classical English story can help your family members learn English

C.going skating can help your family members improve their speaking skills

D.an English family tree can your family members interested in English

问答题 案例分析题

阅读下 * * 段材料:

材料一:《义务教育化学课程标准(2011年版)》的课程内容。

认识常见酸碱的主要性质和用途;认识化学变化的基本特征;初步了解化学反应的本质;知道酸碱性对人体健康和农作物生长的影响;知道利用化学变化可以获得新物质,以适应生活和生产的需要。

材料二:教科书的知识结构体系

第十单元常见的酸和碱

课题1常见的酸和碱

课题2酸和碱之间会发生什么反应

材料三:教科书“酸和碱之间发生化学反应(第一课时)”所呈现的内容:

一、中和反应

【实验】

如图所示,在烧杯中加入10mL氢氧化钠溶液,滴入几滴酚酞溶液。再用滴管慢慢滴入稀盐酸,并不断搅拌溶液,至溶液颜色恰好变成无色为止。

在上边的实验中,发生了如下的反应,生成了氯化钠和水:

实际上,其他的酸和碱也能发生类似的反应。例如:

可以发现,氯化钠、氯化钙和硫酸钠都是由金属离子和酸根离子构成,这样的化合物我们称为盐。盐在水溶液中能解离出金属离子和酸根离子。酸和碱作用生成盐和水的反应,叫做中和反应。

二、中和反应在实际中的应用

中和反应在日常生活和农业生产中有广泛的应用。

1.改变土壤的酸碱性

根据土壤情况,可以利用中和反应,在土壤中加入酸性或碱性物质,以调节土壤的酸碱性,利于植物生长。例如,今年来由于空气污染造成酸雨,导致一些地方的土壤变成酸性,不利于作物的生长,于是人们将适量的熟石灰加入土壤,以中和酸性。

2.处理工厂的废水

工厂生产过程中的污水,需进行一系列的处理。例如,硫酸厂的污水中含有硫酸等杂质,可以用熟石灰进行中和处理。你能写出该反应的化学方程式吗?

3.用于医药

人的胃液里含有适量盐酸,可以帮助消化,但是如果饮食过量时,胃会分泌出大量胃酸,反而造成消化不良。在这种情况下,可以遵医嘱服用某些含有碱性物质的药物,以中和过多的胃酸。

我们都可能被蚊虫叮咬过。被蚊虫叮咬后,叮咬处很快肿成大包,这是因为蚊虫能在人的皮肤内分泌出蚁酸,从而使皮肤肿痛。如果涂一些含有碱性物质(如NH?HO)的药水,就可减轻痛痒。

(摘自某版义务教育课程标准实验教科书《化学》(九年级下)第十单元)

根据上述材料,回答本课题的有关问题:

试对课本内容进行学情分析。