问题 单项选择题

下列有关大理石的叙述,说法不正确的是( )。

A.大理石板材是一种碱性石材,容易被酸侵蚀而影响使用,因此除极少数石材以外,大理石磨光板材一般不宜用于室外饰面

B.大理石是变质岩,主要成分为硫酸盐矿物

C.大理石的化学成分是碳酸钙和碳酸镁

D.大理石质地较密实,属中硬石材

答案

参考答案:B

解析:[考点] 1A413021掌握建筑装饰装修饰面石材、建筑陶瓷的特性与应用 大理石是可以磨平、抛光的各种碳酸盐和与其有关的变质岩,如石灰岩、白云岩、钙质砂岩等,其主要成分为碳酸盐矿物。大理石质地较密实、抗压强度较高、吸水率低、质地较软,属碱性中硬石材。大理石属碱性石材,在大气中受硫化物及水气形成的酸雨的长期作用,容易产生腐蚀,造成表面强度降低、变色掉粉,失去光泽,影响其装饰性能。所以除少数大理石,如汉白玉、艾叶青等质纯、杂质少、比较稳定、耐久的品种可用于室外,绝大多数大理石品种只宜用于室内。

选择题
完形填空

Section B (10分)

Directions: Read the following passage. Answer the questions according to the information given in the passage and required words limit. Write your answers on your answer sheet.

Now let us look at how we read. When we read a printed text, our eyes move across a page in short, jerky movement. We recognize words usually when our eyes are still when they fixate. Each time they fixate, we see a group of words. This is known as the recognition span or the visual span(视幅). The length of time of which the eyes stop ---the duration of the fixation ----varies considerably from person to person. It also varies within any one person according to his purpose in reading and his familiarity with the text. Furthermore, it can be affected by such factors as lighting and tiredness.

Unfortunately, in the past, many reading improvement courses have concentrated too much on how our eyes move across the printed page. As a result of this misleading emphasis on the purely visual aspects of reading, numerous exercises have been devised to train the eyes to see more words at one fixation. For instance, in some exercises, words are flashed on to a screen for, say, a tenth or a twentieth of a second. One of the exercises has required students to fix their eyes on some central point, taking in the words on either side. Such word patterns are often constructed in the shape of rather steep pyramids so the reader takes in more and more words at each successive fixation. All these exercises are very clever, but it’s one thing to improve a person’s ability to see words and quite another thing to improve his ability to read a text efficiently. Reading requires the ability to understand the relationship between words. Consequently, for these reasons, many experts have now begun to question the usefulness of eye training, especially since any approach which trains a person to read isolated words and phrases would seem unlikely to help him in reading a continuous text.

81. Show at least three facts which can affect the time of the recognition span. (no more than 14 words)(2分)

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82.what does reading require according to the writer?(no more than 8 words)(2分)

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83. What is the attitude of the author towards reading improvement courses mentioned in the passage? ( one word )  (3分)

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84. What will probably the writer talk about next? (no more than 12 words)(3分)

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