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    Wool is used clothes. A.for making B.for make C.as D.to making 答案:A 固定搭配be used for意思是“被用来?做--? .for是介词后面要用动词的现在分词形式.所以B项不对.选项C不符合句子的意思“木头被用来做衣服 . D项to后面要用动词原形. 【查看更多】

     

    题目列表(包括答案和解析)

    Wool is used ________ clothes．


    1. A.
      for making
    2. B.
      for make
    3. C.
      as
    4. D.
      to making

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    A Simple Scientific Experiment

    Below is a description of a single scientific experiment. It shows us how iron reacts ( 反应) with air and with water.
    Aim : To find out if iron rusts( 生锈) (a) in dry air ; (b) in water that has no air in it ( air- free water) ; (c) in ordinary water.
    Materials : 3 clean iron nails ( 铁钉) ; test tubes ; test tube holder ; cotton wool ; oil ; Bunsen burner.
    Iron in dry air
    Method
    (1)Put some iron nails at the bottom of a test tube.
    (2)Push some cotton wool down the tube.
    (3)Leave the tube for one week.
    Result
    After one week, the nails have not rusted.
    Conclusion
    Iron does not rust in dry air.
    Iron in air-free water
    Method
    (1)Half-fill a test tube with water.
    (2)Boil the water for three minutes. (This makes sure there is no air in the water.
    (3)Put two or three clean nails in the water.
    		(4)Add some oil to the water. (This will keep air out of the water.)
    (5) Leave the tube for one week.
    Result
    The nails do not rust in the tube with air-free water.
    Conclusion
    Iron does not rust in air- free water.
    Iron in ordinary water
    Method
    (1)Half –fill a test tube with water and add two or three clean nails.
    (2)Leave the tube for one week.
    Result
    The nails rust in the tube with ordinary water.
    Conclusion
    Iron rusts in ordinary water. (238 words)
    【小题1】In the first part of the experiment the cotton wool is most probably used to ______________.
    A．keep the air dryB．keep the tube wet
    C．make the nails rustD．keep the tube clean
    【小题2】What are necessary steps to make sure the water in the tube is air free?
    ①Leave half a tube of water in it              
    ②Boil the water for some time
    ③Put some clean iron nails in the tube           
    ④Add some oil to the water
    A．①②B．①③C．②③D．②④
    【小题3】We can conclude from the experiment that only ____________ makes iron rusty.
    A．dry airB．cotton woolC．ordinary waterD．air-free water

    查看答案和解析>>

    A Simple Scientific Experiment

    Below is a description of a single scientific experiment. It shows us how iron reacts ( 反应) with air and with water.

    Aim : To find out if iron rusts( 生锈) (a) in dry air ; (b) in water that has no air in it ( air- free water) ; (c) in ordinary water.

    Materials : 3 clean iron nails ( 铁钉) ; test tubes ; test tube holder ; cotton wool ; oil ; Bunsen burner.

    Iron in dry air

    Method

    (1) Put some iron nails at the bottom of a test tube.

    (2) Push some cotton wool down the tube.

    (3) Leave the tube for one week.

    Result

    After one week, the nails have not rusted.

    Conclusion

    Iron does not rust in dry air.

    Iron in air-free water

    Method

    (1) Half-fill a test tube with water.

    (2) Boil the water for three minutes. (This makes sure there is no air in the water.

    (3) Put two or three clean nails in the water.

    (4)Add some oil to the water. (This will keep air out of the water.)

    (5) Leave the tube for one week.

    Result

    The nails do not rust in the tube with air-free water.

    Conclusion

    Iron does not rust in air- free water.

    Iron in ordinary water

    Method

    (1) Half –fill a test tube with water and add two or three clean nails.

    (2) Leave the tube for one week.

    Result

    The nails rust in the tube with ordinary water.

    Conclusion

    Iron rusts in ordinary water. (238 words)

    1.In the first part of the experiment the cotton wool is most probably used to ______________.

       A. keep the air dry                            B. keep the tube wet

       C. make the nails rust                          D. keep the tube clean

    2.What are necessary steps to make sure the water in the tube is air free?

    ①Leave half a tube of water in it              

    ②Boil the water for some time

    ③Put some clean iron nails in the tube           

    ④Add some oil to the water

      A. ①②                  B. ①③                 C. ②③                D. ②④

    3.We can conclude from the experiment that only ____________ makes iron rusty.

    A. dry air       B. cotton wool           C. ordinary water         D. air-free water

     

    查看答案和解析>>

    A Simple Scientific Experiment
    Below is a description of a single scientific experiment. It shows us how iron reacts ( 反应) with air and with water.
    Aim : To find out if iron rusts( 生锈) (a) in dry air ; (b) in water that has no air in it ( air- free water) ; (c) in ordinary water.
    Materials : 3 clean iron nails ( 铁钉) ; test tubes ; test tube holder ; cotton wool ; oil ; Bunsen burner.
    Iron in dry air
    Method
    (1)Put some iron nails at the bottom of a test tube.
    (2)Push some cotton wool down the tube.
    (3)Leave the tube for one week.
    Result
    After one week, the nails have not rusted.
    Conclusion
    Iron does not rust in dry air.
    Iron in air-free water
    Method
    (1)Half-fill a test tube with water.
    (2)Boil the water for three minutes. (This makes sure there is no air in the water.
    (3)Put two or three clean nails in the water.
    		(4)Add some oil to the water. (This will keep air out of the water.)
    (5) Leave the tube for one week.
    Result
    The nails do not rust in the tube with air-free water.
    Conclusion
    Iron does not rust in air- free water.
    Iron in ordinary water
    Method
    (1)Half –fill a test tube with water and add two or three clean nails.
    (2)Leave the tube for one week.
    Result
    The nails rust in the tube with ordinary water.
    Conclusion
    Iron rusts in ordinary water. (238 words)
    小题1:In the first part of the experiment the cotton wool is most probably used to ______________.
    A．keep the air dryB．keep the tube wet
    C．make the nails rustD．keep the tube clean
    小题2:What are necessary steps to make sure the water in the tube is air free?
    ①Leave half a tube of water in it              
    ②Boil the water for some time
    ③Put some clean iron nails in the tube           
    ④Add some oil to the water
    A．①②B．①③C．②③D．②④
    小题3:We can conclude from the experiment that only ____________ makes iron rusty.
    A．dry airB．cotton woolC．ordinary waterD．air-free water

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    阅读理解。
    A Simple Scientific Experiment
    Below is a description of a single scientific experiment  . It shows us how iron reacts ( 反应) with air and
    with water.
    Aim : To find out if iron rusts( 生锈) (a) in dry air ; (b) in water that has no air in it ( air- free water) ; (c)
    in ordinary water.
    Materials : 3 clean iron nails ( 铁钉) ; test tubes ; test tube holder ; cotton wool ; oil ; Bunsen burner.
    Iron in dry air
    Method
    (1)Put some iron nails at the bottom of a test tube.
    (2)Push some cotton wool down the tube.
    (3)Leave the tube for one week.
    Result
    After one week, the nails have not rusted.
    Conclusion
    Iron does not rust in dry air.
    Iron in air-free water
    Method
    (1)Half-fill a test tube with water.
    (2)Boil the water for three minutes.( This makes sure
    there is no air in the water.
    Put two or three clean nails in the water.    		 (4)Add some oil to the water. ( This will keep
    air out of the water.)
    (5) Leave the tube for one week.
    Result
    The nails do not rust in the tube with air-free
    water.
    Conclusion
    Iron does not rust in air- free water.
    Iron in ordinary water
    Method
    (1)Half -fill a test tube with water and add two
    or three clean nails.
    (2)Leave the tube for one week.
    Result
    The nails rust in the tube with ordinary water.
    Conclusion
    Iron rusts in ordinary water.          
    1.  In the first part of the experiment the cotton wool is most probably used to ______________.        
    A. dry air                  
    B. cotton wool          
    C. ordinary water        
    D. air-free water
    2. What are necessary steps to make sure the water in the tube is air free?
    ①Leave half a tube of water in it                ②Boil the water for some time
    ③Put some clean iron nails in the tube        ④Add some oil to the water
      A. ①②                  B. ①③                 C. ②③                D. ②④
    3. We can conclude from the experiment that only ____________ makes iron rusty.
    A. keep the air dry                            
    B. keep the tube wet
    C. make the nails rust                          
    D. keep the tube clean

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