题干

下列关于氯水的叙述正确的是(  )

A:新制氯水中只含Cl2和H2O

B:将镁粉加入新制氯水中无明显变化

C:氯水放置一段时间后颜色将变深

D:新制氯水可使紫色石蕊试液先变红后褪色

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答案(点此获取答案解析)

D

同类题3

根据短文内容,选择最佳答案。

    People use their mouths for many things. They eat, talk, shout and sing. They smile and they kiss. In the English language, there are many expressions about the word “mouth”. But some of them are not so nice.

    For example, if you say bad things about a person, the person might protest and say “Do not bad mouth me.”

    Sometimes, people say something to a friend or family member that they later regret because it hurts that people's feelings. Or they tell the person something they were not supposed to. The speaker might say: “I really put my foot in my mouth this time”. If this should happen, the speaker might feel down in the mouth, In other words, he might feel afraid for saying the wrong thing.

    Sometimes when one person is speaking, he says the same thing that his friend was going to say. When this happens, the friend might say: “You took the words right out of my mouth!” Sometimes a person has a bad or unpleasant experience with another person. He might say that experience “left a bad taste in my mouth”. Or the person has possibly had a very scary experience, like being chased by an angry dog. He might say, “ I had my heart in my mouth.”

    Some people have lots of money because they were born into a very rich family. There is an expression for this, too. You might say such a person “was born with a silver spoon in his mouth”. This rich person is the opposite of a person who lives from “hand to mouth”. This person is very poor and only has enough money for the most important things in life, like food.

同类题4

阅读理解

冬口北国鸟

徐培学

    ①一日里,北方的麻雀是值得我们把它当作鹰来看待的。

    ②数九寒天,麻雀用一抹褐色,氤氲着不屈的情怀,在枝头曼妙地摇曳,温暖着我们的心情。它们是寒风中光秃秃的枝梢上印象派的花朵,用小小的身姿,俯仰间点缀着清冷的时光。

    ③麻雀原本是再普通不过的鸟儿,它形不惊人,声不迷人,平凡得像坊间的小狗小猫和一大片叫狗蛋的孩子。

    ④但麻雀又是值得我们敬重的。冬日麻雀最值得称颂的是它的坚守,与生它养它的土地不离不弃。麻雀——孤独的舞者,在北方冬日的天幕下,跳着并不优美但还算是灵动的舞。

    ⑤麻雀的聒噪,源于它们严寒中坚守的孤独。此时,鸟儿们都在冬日里噤了声,除了麻雀,谁还会来活跃冬日的气氛?

    ⑥忘记说一句,麻雀也叫北国鸟。

    ⑦不管首肯与否,我们都不得不承认,麻雀是城乡冬日里最活跃的意象,夸张一点说,麻雀几乎是冬日天空中唯一活跃的意象。

    ⑧冬日,皑皑白雪覆盖了一切,麻雀们如何寻找果腹的东西呢?冬日的麻雀是素食主义者,只能以草籽果腹。这个时候,人,乘虚而入,在雪地里,支上一只箩筐,下面撒上点谷粒,就等着麻雀上钩。那些不幸落入人手中的麻雀,任你威逼利诱,不吃不喝,目不斜视,视死如归。

    ⑨有人说:麻雀是动物界中最后的烈女。此话不假,麻雀不媚人,特立独行,是公认的唯一不向人类屈服的鸟儿。

    ⑩今天上午,我正在书房里写字,听到阳台上麻雀们欢快的叫声。抬头,隔了窗上的玻璃,就见十几只麻雀拥拥挤挤地站在窗台上,你挤我挨。像一串跃动的音符。间或一直丛墨自得地梳理着诅毛,还会忙中偷闲地跟伙伴们整理妆容。

    ⑪饭后外出,走在路上,就有一群麻雀落在我的身前,我往前走,它们就往后退,等到我前进的速度足以大过它们跳跃着后退的速度时,它们便旋风般地飞起来,然后降落,再次在前面迎候着我。

   ⑫想起去法国巴黎旅游时,在广场上,那几只站在我手上的麻雀,鑫焦惆怅;如果这群麻雀也会站在我的手上,哪怕只有一只。只有短短的一秒,那该多好啊!

   ⑬它会站在我的手上吗?

   ⑭鸟类学家亨德森说:  “如果没有鸟类的作用,人类就不能在地球上生存!”

   ⑮仿佛是突然间,我心里打一冷战:某一天,没有麻雀陪伴,我们的生活是一个什么样子呢?我有些惶恐。