1--Are these books on sale?   

2--There's a 20% discount for members only.       

1--How can I get the membership? 

2--That's very easy. Just fill in this application form. 

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注解：
 
1.on sale打折
2.membershi会员
3.application申请表

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译文：

1--这些书打折吗？   
2--只对会员打八折。     
1--我怎样才能成为会员呢？       
2--非常容易。填张申请表就行了。