Chen Hao brings back a pair of shoes that are too small. The assistant wants to know whether he has worn them outside.
Chen Hao
您好，上个星期在这儿买的鞋，我想退。
Nín hǎo, shàng gè xīngqī zài zhèr mǎi de xié, wǒ xiǎng tuì.
Hello, I would like to return the shoes I bought here last week.
The shop assistant
是哪儿不合适？
Shì nǎr bù héshì ?
What is wrong with them?
Chen Hao
买回去才发现小了一号，穿着不舒服。
Mǎi huíqu cái fāxiàn xiǎo le yī hào, chuān zhe bù shūfu.
Only when I got home did I see they were a size too small, they pinch.
The shop assistant
您在外面穿过吗？穿过的鞋不能退。
Nín zài wàimian chuān guò ma ? Chuān guò de xié bù néng tuì.
Have you worn them outside? Shoes that have been worn cannot be returned.
Chen Hao
只在家里试过两次，一直放在盒子里。
Zhī zài jiā lǐ shì guò liǎng cì, yīzhí fàng zài hézi lǐ.
I only tried them on twice at home, they have been in the box ever since.
The shop assistant
小票带来了吗？
Xiǎo piào dài lái le ma ?
Have you brought the receipt?
Chen Hao
带来了，还有手机上的短信。
Dài lái le, háiyǒu shǒujī shàng de duǎnxìn.
I have, and the text message on my phone as well.
The shop assistant
好的。您是想退钱，还是换一双大的？
Hǎo de. Nín shì xiǎng tuì qián, háishi huàn yī shuāng dà de ?
Very good. Would you like a refund, or to exchange them for a larger pair?
Chen Hao
换一双吧。你们还有四十三号的吗？
Huàn yī shuāng ba. Nǐmen háiyǒu sìshísān hào de ma ?
An exchange, please. Do you still have a forty-three?
The shop assistant
有，不过黑色的只有一双了。
Yǒu, bùguò hēisè de zhī yǒu yī shuāng le.
We do, but there is only one pair left in black.
Chen Hao
黑色的也行，就换这双。
Hēisè de yě xíng, jiù huàn zhè shuāng.
Black is fine, I will take that pair.
穿过吗 does not ask whether you wear them, nor whether you wore them at a particular moment, but whether you have ever done so. It is 过 that says experience, and it goes immediately after the verb. The negative takes 没 and keeps 过: 没穿过, never worn. Do not confuse it with 了, which reports a dated fact: 昨天穿了, I wore them yesterday.
In a question, "or" is 还是: 退钱还是换一双, refund or exchange. In a statement it is 或者: 退钱或者换一双都可以. Using 或者 in a question is the most regular beginner's mistake, and it is heard at once.
买回去才发现 says the discovery came too late, once he was home. 才 goes before the verb and always marks a lag: it is the exact opposite of 就, which says a thing happened earlier than expected. 八点才到 means he did not get there until eight; 八点就到了 means he was there as early as eight.
