搜题请搜索小程序“爱下问搜题”
问题 选择题

让杂合子Aa连续自交三代，则第四代中杂合子所占比例为[ ]

A．1/4

B．1/8

C．1/16

D．1/32

答案

答案：B

单项选择题 B型题

钩虫病的主要防治措施是（）

A.加强粪便管理、注意饮食卫生

B.勿食未熟的猪肉

C.避免用鲜粪施肥和赤脚下田劳作

D.注意个人卫生，防止再感染

E.防蚊叮咬、灭蚊
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改错题
短文改错。改正下列短文中的错误。请根据上下文对标有题号的每一行作出判断；如无错误，
在该行右边横线上划一个勾（√）；如有错误（每行只有一个错误），则按下列情况改正；
此行多一个词：把多余的词用斜线（\）划掉，在该行右边横线上写出该词，并用斜线划掉。
此行缺一个词：在缺词处加一个漏字符号（∧），在该行右边横线上写出应加的单词。
此行错一个词：在错词下划一道线，在该行右边横线上写出改正后的单词。
注意：原行没有错误的不要改。
Should students make friends on line? Some of people say yes.       
The Internet helps make many friends. Chat on line,              
students can more free express their feelings and opinions,       
and even get help with their foreign languages studies. Others,    
therefore, think students should not. They say making friends      
on line is waste of time, which should be spent more             
meaningfully on study. Beside, some students get cheat?ed on line.  
It is my opinion students should place their study, health         
and safety before the other things. As for friendship, we can         
readily find them in our classmates and other people around us.    		1. ________   
2. ________    
3. ________     
4. ________  
5. ________    
6. ________                             
7. ________   
8. ________    
9. ________     
10. ________  
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