2 sentences

1. 买家负责邮费。

   mǎi​jiā fù​zé yóu​fèi.

   The buyer is responsible for postage costs.

   Source: CCMatrix

2. 寄往加拿大的航空信要多少邮费？

   jì wǎng jiā​ná​dà de háng​kōng​xìn yào duō​shao yóu​fèi?

   How much is the postage for an airmail letter to Canada?

   Source: UM-Corpus: Spoken