30% discount意思是打七折，20% discount意思是打八折。例句：It's nice, but still too expensive. Can you give me a 20% discount?是不错。但还是太贵了。能打八折吗？
discount例句
1.discontinued ranges of tiles at discount prices
折价出售的已停产瓷砖
2.This has forced airlines to discount fares heavily.
这迫使航空公司将机票大幅打折。
3.This should have triggered the discount.
这应该触发折扣生效。
4.I can discount ten per cent for you.
我可以给你打九折。
5.discount fares of around ￡360 return
返还360英镑左右的折扣票价
短语搭配
quantity discount数量折扣；大批量折扣；折扣量；高额保险折扣优惠
special discount[物价]特别折扣；特价区；特扣；出格扣头
extra discount额外折扣；额外成本
discount liability折价债务
volume discount总购量折扣；数量折扣；批发折扣