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问题 解答题

仔细观察大多数植物叶片的正面绿色较深而背面绿色较浅，主要原因是______．

答案

叶片的表皮包括上表皮和下表皮，靠近上表皮的叶肉细胞呈圆柱形，排列整齐，称为栅栏组织，细胞里有较多的叶绿体；接近下表皮的叶肉细胞形状不规则，排列疏松，称为海绵组织，细胞里含叶绿体较少．因此叶片正面颜色深、背面颜色浅．

故答案为：靠近上表皮的叶肉（或靠近正面的栅栏组织）中含有较多的叶绿体

单项选择题 A1/A2型题

有关双端固定桥的应力分析说法错误的是（）。

A.双端固定桥基牙的应力分布最均匀

B.桥体下的牙龈组织也分担了极少量的载荷

C.对水平向载荷的承受能力较小

D.两端基牙分担的力相同

E.应增加支持力较弱侧的基牙数目
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填空题


A good translator is by definition bilingual. The opposite is not (1) true, however. A born and bred bilingual will still need two (2) to become a translator: first, the skills and experience necessary for (3) ; second, knowledge of the field in which he or she will (4) . The skills and experience for translation include the ability to write (5) in the target language, the ability to read and understand the (6) language material thoroughly, and the ability to work with the latest (7) and communication hardware and software.
Does a born and bred bilingual (8) a better translator than someone who learned language B later in (9) There is no definite answer, but the following issues are important. (10) , a born and bred bilingual often suffers from not truly knowing (11) language well enough to translate, with some even suffering from what (12) known as a lingua-ism, a state in which a person lacks (13) full, fluent command of any language. Second, born and bred bilinguals (14) don’t know the culture of the target language well enough to (15) top-quality translations, or cannot recognize what aspects of the source language (16) its culture need to be treated with particular care, as they (17) in a sense too close to the language. And last, they often (18) the analytical linguistic skills to work through a sticky text.
On (19) other hand, the acquired bilingual may not have the sam0e in-depth (20) of colloquialisms, slang, and dialect that the born bilingual has. Also, the acquired bilingual will not be able to translate as readily in both directions (from B to language A and A to language B). Finally, born bilinguals often have a greater appreciation of the subtleties and nuances of both their languages than someone who learns their B language later in life can ever hope to have.
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