21.我爸没有姐妹.___________________ 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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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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根据汉语意思补全英语句子。每空词数不限。
【小题1】他参加了去年的小提琴比赛。
He ___________________________ the violin competition last year.
【小题2】我爸睡过头了,没有赶上早班车。
My father ___________________________ and didn’t catch the early bus.
【小题3】上周的才艺展示获得了巨大成功。
Last week’s talent show was ___________________________.
【小题4】这儿有给你的一些如何学好英语的建议。
Here ___________________________for you on how to learn English well.
【小题5】我们应多锻炼以保持健康。
We should often exercise ___________________________.

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根据汉语意思补全英语句子。每空词数不限。

1.他参加了去年的小提琴比赛。

He ___________________________ the violin competition last year.

2.我爸睡过头了,没有赶上早班车。

My father ___________________________ and didn’t catch the early bus.

3.上周的才艺展示获得了巨大成功。

Last week’s talent show was ___________________________.

4.这儿有给你的一些如何学好英语的建议。

Here ___________________________for you on how to learn English well.

5.我们应多锻炼以保持健康。

We should often exercise ___________________________.

 

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任务型阅读
       Hello!  My name is Peter. I am 12 years old. My father'is a doctor, His name is John. My mother's
name is Chris. I love them very much. I have no brothers or sisters. Betty,Mary and Yokiko are my
friends. Betty is 13. She has one brother. His name is Norman. Mary is 13, too.  Mary has two brothers
and a sister. Her sister's name is Rose. Her parents are Colin and Amy. Yokiko is young. She is two years younger(小两岁)than Mary. And she is a Japanese girl. She has one brother and one sister. Her sister's
name is Haruko. She is very cute.
根据短文内容完成下表
Name Age Father Mother Brother(s) Sister(s)
Peter _
Betty Alan Peggy _
Mary 13 Colin Tom&Jim
Yokikd Kuro Naomi Takeshi

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