用特殊的方法 in a special way 【查看更多】

 

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萘乙酸(NAA)是科学家通过化学的方法合成和筛选的在结构和生理作用方面与生长素相似的物质,其生理作用也与浓度密切相关,探究萘乙酸(NAA)对扦插枝条生根作用的最佳浓度范围,在农业生产的应用上具有非常重要的意义。
 一、实验原理:
萘乙酸与生长素一样,对植物生长的调节作用具有___________________________性,即
_______________________________________________________________。(2分)
二、实验过程与方法:
(1)取材;取山茶花植株生长良好的半木质枝条,剪成5—7cm,每段插条芽数相同。
(2)实验:①将插条分别用不同的方法处理如图1;②将处理过的插条下端浸在清水中,注意保持温度(25~30℃)。
(3)记录:小组分工,根据实验数据,建立数学模型如图2。
三、结果分析与评价:
(1)从图2中,可得出的结论是_________________________________________          。
(2)插条若没有生出不定根,其原因最可能是____________________________            。
(3)温度、处理时间等要一致,其原因是_________________________________           。
(4)每组都选取10根插条,其目的是____________________________________           。

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Complete the dialogue with proper words or sentences according to the meaning of the dialogue. (根据对话内容,用适当的词语或句子补全对话。)

A:Zhang Mei, come here, please. Look at this traveling book.

B:What? Traveling book? We should read subject books, not traveling books.

1   for high school, you know.

A: Of course I know, but after the exam I want to go to Harbin for a trip. 2   ?

B:Yes. I've been there twice.

A:Really? 3   ?

B:Exciting and attractive!

A:What's there to see and play?

B:Well. 4   . You can go to the Sun Island, visit the St. Sophia Church, take a walk and do some shopping in Zhongyang Walking Street. There are many old buildings there. If you want to see the whole city, you can go to the Dragon Tower(龙塔).

A:That 5   !

B:Oh, you can also go to the Songhua River. There you can fly kites, go fishing, go swimming and go boating. Many activities to attend.

A:Is that true? I can't wait for that!

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阅读理解

My name is Ted Pike. I am a worker in a big shop. I don't work in the morning: I only work at night. Every morning I come home at about half past six. I eat breakfast at seven. After breakfast I go to bed. I get up at half past two. I eat lunch at a quarter to three and supper at twenty to eight. Then I go to work at a quarter past eight. I start work at nine. I look after the shop every night. I like my work very much.

1.根据短文内容用适当的词填空。

(1)Ted Pike is a ________ in a big shop.

(2)He gets up at ________ in the ________.

(3)He starts work at ________ in the evening.

(4)He comes home at ________ in the ________.

2.阅读上面的短文,然后判断下列句子的正(T)误(F)。

(1)Ted works in the morning.

(  )

(2)Ted sleeps(睡觉)at 6:30 a. m.

(  )

(3)Ted doesn't work at 12 p. m.

(  )

(4)Ted goes to work at 8:15 p. m.

(  )

(5)Ted is at home in the morning.

(  )

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根据对话内容,用适当的词语或句子补全对话。

A:Good morning!  1  

B:I’d like to buy an MP4 for my English study.

A:We have many here.Which one do you like?

B:This one looks nice.  2  

A:It’s made in Guangzhou.

B:  3  ?

A:It’s 2000 yuan.

B:  4  too expensive.Have you got a cheaper one?

A:Sure.This red one costs only 300 yuan.

B:OK.I’ll take it.  5   is the money.

A:Thanks.

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阅读理解

  Our earth is in trouble.Our drinking water is becoming dirtier, and the air is not as clean as before.People and factories are polluting the air, rivers and lakes and seas.You may think that there is mothing you can do to help.That's not true.There are many things you can do to help the earth.

  Cars burn gasoline.This will produce a lot of CO2 into the air.Some people believe that too much CO2 is making the earth warmer than ever.They think CO2 thins the clouds above us.The clouds keep us away from the strongest sunlight.So try to walk, ride a bike or take a bus.And if you drive a car, drive at a steady speed.This can save some gasoline.

  The biggest energy use at home is for keeping warm and cool.So turn the air conditioner off when you don't need to use it.Use lights that save energy.

  Use fewer things that cannot be used again.When you buy something, consider those made from things that can be used again first.

  (1)要用大量的水来洗澡沐浴.In one week an American family uses as much water for showers as a person drinks in three years! Buy a waterworks that uses less water, or take shorter showers.This can cut the use of water.

1.将(1)处译成英语.

____________________________

2.找出 If there is too much CO2 in the air, the earth will become warmer 的同义句.

____________________________

3.从文中找出能概括本文大意的句子.

____________________________

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