8.在中间______________ 9.在右边____________ 查看更多

 

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炭疽热是由炭疽芽孢杆菌引起的,该细菌可引起动物组织水肿、粘膜出血,幷可造成动物死亡。法国科学家巴斯德在研究牲畜炭疽病时进行了如下实验:给实验绵羊注射毒性已削弱的炭疽芽孢杆菌制剂,这些绵羊感染后没有发病。四天后,给实验绵羊注射毒性极强的炭疽芽孢杆菌制剂,经过一段时间后,实验绵羊全部正常生活。根据以上资料,回答以下问题。
(1)实验绵羊在第二次注射炭疽芽孢杆菌制剂后没有发病,其原理是体内产生____,该物质的化学本质是____,它是由____细胞产生分泌的。与之合成和分泌相关的细胞器有____________,这种免疫属于____免疫。
(2)如果不能确定第二次注射的炭疽芽孢杆菌对实验绵羊的毒性是否极强,需要改进实验设计,请在上述实验的基础上补充相应的实验设计原则、步骤。
①实验设计原则:____________
②操作步骤:____________

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介词。
1.在早上   _ the morning
2.在学校   _ school
3.八点钟   _ 8:00
4.在1989年  _ 1989
5.在星期天   _ Sunday
6.为…感谢   thanks _
7.在某方面帮助   help… __
8.与…一起玩   play _
9.通过电视   _ TV
10.在地板上   _ the floor
11.把...带到   take … _ …
12.全家福   a photo _ family

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Cinderella has to do all the housework. She makes the beds. She watches the clothes. She cleans the room. She __ the meals. She goes shopping_____the family.

One day, the family goes to a __ at the prince’s palace (皇宫). Cinderella is __. She says, “I want to go and dance, too! ”

Then, a fairy(仙女) comes and says, “I can help you. ” She gives Cinderella a party dress and a pair of glass __. Then she says, “Come home early. You must get home before 12:00___”

Cinderella goes to the party and __ with the prince. She forgets about the__. Then she sees a clock. It is almost midnight. Cinderella __ home and she gets home right at 12:00, ______she loses one of her glass shoes on the way.

1.AeatsBmakes Cbuys Dgives

2.AwithBup Cin Dfor

3.ApartyBmovie Cpicnic Dtrip

4.ArelaxingBbusy Chappy Dboring

5.Ashoes Bhats Cpants Dgloves

6.Ain the moringBin the afternoon Cin the evening Dat night

7.A. sings B. dances C. plays D. talks

8.AclothesBhousework Cmusic Dtime

9.Agoes Bwalks Ctakes Druns

10.Abut Band Cso DBecause

 

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David,an __boy can write in Chinese.

A. 8_years_old   B. 8_years   C. 8_year_old   D. 8_years old

 

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Cinderella has to do all the housework. She makes the beds. She watches the clothes. She cleans the room. She __ the meals. She goes shopping_____the family.
One day, the family goes to a __ at the prince’s palace (皇宫). Cinderella is __. She says, “I want to go and dance, too! ”
Then, a fairy(仙女) comes and says, “I can help you. ” She gives Cinderella a party dress and a pair of glass __. Then she says, “Come home early. You must get home before 12:00___”
Cinderella goes to the party and __ with the prince. She forgets about the__. Then she sees a clock. It is almost midnight. Cinderella __ home and she gets home right at 12:00, ______she loses one of her glass shoes on the way.
小题1:
A.eatsB.makesC.buysD.gives
小题2:
A.withB.upC.inD.for
小题3:
A.partyB.movieC.picnicD.trip
小题4:
A.relaxingB.busyC.happyD.boring
小题5:
A.shoesB.hatsC.pantsD.gloves
小题6:
A.in the moringB.in the afternoon C.in the eveningD.at night
小题7:
A. singsB.dancesC.playsD.talks
小题8:
A.clothesB.houseworkC.music D.time
小题9:
A.goesB.walksC.takes D.runs
小题10:
A.butB.andC.soD.Because

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