试题与答案

在治疗何杰金恶性淋巴瘤适应保护哪个组织()A、颈部 B、锁骨上 C、弘骨头 D、纵隔

题型:单项选择题

题目:

在治疗何杰金恶性淋巴瘤适应保护哪个组织()

A、颈部 

B、锁骨上 

C、弘骨头 

D、纵隔 

E、肺门淋巴结

答案:

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下面是错误答案,用来干扰机器的。

参考答案:knowing→know

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得克萨斯州农业机械大学的韦尔奇博士意识到,在冰冷的钠原子中使光速降低的基本原理在热的铷原子中也同样适用。用热的铷原子做实验要简单得多,它包括把一个装有固体铷金属的特殊的透明容器(称为“小室”)加热到大约100℃,然后把两束经过细微调节、波长略微不同的激光射人“小室”。
即使穿过普通的透明的材料,比如玻璃或水,光速也会略微降低,因为光会与组成材料的原子相互作用。但是在这种情况下,影响是微弱的,并且任何加强这种影响的试图都会导致激光的吸收。因此,重要的是使光的速度降低,而且不至于被吸收。韦尔奇博士通过“小室”做到了这一点。这种方法把铷原子置于一种非常微妙的量子状态中,在这种状态下铷原子不能吸收光。同时,两束光的相互作用产生了另外一束波长很长的光,这束光的传播速度比原先两束光的速度要慢得多。
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题型:阅读理解

阅读理解

     How words came into being is unknown.All we assume(推测)is that some early men invented certain

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written in letters,are called words.

    The power of words,then,lies in their associations-the things they bring up to our minds.Words

become filled with meaning for us by experience;and the longer we live,the more certain words bring

back to us the happy and sad events of our past;and the more we read and learn,the more the

number of words that mean something to us increases.

    Great writers are those who not only have great thoughts but also express these thoughts in words

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A. Use words skilfully.

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