2 sentences

1. 我讨厌写感谢信。

   wǒ tǎo​yàn xiě gǎn​xiè​xìn.

   I hate writing thank-you notes.

   Source: OpenSubtitles

2. 他在离职前给每位同事致了感谢信。

   tā zài lí​zhí qián gěi měi wèi tóng​shì zhì le gǎn​xiè​xìn.

   Before leaving, he sent a letter of thanks to each of his colleagues.

   Source: Dong Chinese Dictionary