Tickets are not refundable.

不能退票。

《牛津词典》

Empty bottles are not refundable.

空瓶不退。

《新英汉大辞典》

I'm sorry. They are not refundable.

对不起，它们是不能退的。

youdao

Taxpayers in 2012 can claim the adoption credit but it is not refundable.

FORBES: 11 Changes You Must Know Before Filing Your Tax Return for 2012

Since the federal child-care tax credit is not refundable, it does little for those who do not earn enough to pay federal income tax.

ECONOMIST: Out of sight, out of mind

Similarly, most corporate sponsorship packages and hospitality suites are secured long before now and are generally not refundable or conditional upon certain athletes appearing in the event.

FORBES: Tiger's Absence Should Have Little Financial Impact On U.S. Open