3 sentences

1. 谨具薄酒，不成敬意。

   jǐn jù bó​jiǔ, bù chéng jìng​yì.

   I have prepared this simple wine as a small token of my respect.

   Source: Dong Chinese Dictionary

2. 我谨向你表示诚挚的谢意。

   wǒ jǐn xiàng nǐ biǎo​shì chéng​zhì de xiè​yì.

   I would like to express my sincere gratitude to you.

   Source: Dong Chinese Dictionary

3. 谨代表全体员工向您致以诚挚的问候。

   jǐn dài​biǎo quán​tǐ yuán​gōng xiàng nín zhì​yǐ chéng​zhì de wèn​hòu.

   On behalf of all employees, I would like to extend sincere greetings to you.

   Source: Dong Chinese Dictionary