5. Do you have a receipt?
您有收据吗？
还能这样说：
Can I have a look at your receipt?
Do you have a receipt for it?
应用解析：
acknowledge the receipt of 确信收到；
be in receipt of 收到；
at the receipt of custom 在海关；
receipt for sth. 收条，收据；
receipt of sth. 收到
6. We only take goods back if you can produce the receipt.
只有你出示收据，我们才能予以退货。
还能这样说：
Showing the receipt, you can refund the goods.
If you don't show us the receipt, we can't take goods back.
7. You may exchange the skirt but not return it for a refund.
你可以调换这条裙子，但不能退货。
还能这样说：
You can exchange the skirt but you can't return it.
We can't take the skirt back, but you can exchange it.
8. I want to exchange the blue jumper into a red one.
我想把这件蓝色的毛衣换成红色的。
还能这样说：
I want to replace the blue jumper with red.
I would like to have a red jumper instead of the blue one.
应用解析：
jumper 其他的意思有：跳跃者；雪橇；（工人，水手等的）工作服；穿在衬衣外面的无袖连衣裙。