题目内容

17．在床上看书对你的眼睛有害处．Reading in bedis bad for your eyes．

分析 is bad for

解答 答案：is bad for．
首先通过中英文句子的比对，可知英文句子中缺少"对…有害"的表达．短语"对…有害"的英文表达是：be bad for．本题中，句子表述的一般性的事实，所以用一般现在时，另外注意动名词作主语视为单数，故答案为：is bad for

点评 做这类题型，首先根据所给汉语明确句子所要考查的单词或短语的拼写，再结合相关语法知识对单词或短语做出形式上的变化．

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The immune system is more powerful than you probably imagine．Scientists from the University of Pennsylvania recently took immune cells from three patients with leukemia，then genetically cheanged them into"serial Keller"cells to attack cancer cells．The study was small but the results were groundbraking．The modified immune cells increascd at least 1，000 times in the body and killed all the cancer cells．Therefore，more"memory cells"were created．
  The immune system can be developed．Eating lean protein food （beef，beans ）and food rich in vitamins A，C，and E（sweet potatoes，carrots ），taking a 30-minute walk every day and reducing your stress levels，etc．will help you achieve it．

37．What can the immune system do？B
A．Keep you from antibodies．
B．Protect you against antigens．
C．Make your bodies werk and sick．
D．Help microbes enter your bodies
38．How are the sneaky antigens found and killed？A
A．Phagocytes，B，T helper and T killer cells work together
B．Skin，tears，acidic juice and immune cells work together
C．B cells create"memory cells"to swim around in the blood
D．B cells produce antibodies to tell T helper and T killer cells
39．What does the underlined word"it"in the last paragraph refer to？A
A．The immune system can be made more powerful
B．Less antigens can be killed by the immune system
C．White blood cells act less quickly in the immune system
D．The immune system can be changed into the"serial killer"
40．This article is mainly aboutD．
A．the types of white blood cells
B．a research report about human healeh
C．the cause of illness and discase
D．an introduction to the immune system．

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