6 sentences

1. 密国是周朝的一个诸侯国。

   Mì​guó shì Zhōu​cháo de yī gè zhū​hóu​guó.

   Mi was a vassal state of the Zhou Dynasty.

   Source: Dong Chinese Dictionary

2. 陈国是周代的一个诸侯国。

   Chén​guó shì Zhōu​dài de yī gè zhū​hóu​guó.

   Chen was a vassal state during the Zhou Dynasty.

   Source: Dong Chinese Dictionary

3. 薛国是周朝的一个诸侯国。

   Xuē​guó shì Zhōu​cháo de yī gè zhū​hóu​guó.

   The State of Xue was a vassal state of the Zhou Dynasty.

   Source: Dong Chinese Dictionary

4. 卫国在周朝时期曾是一个诸侯国。

   Wèi​guó zài Zhōu​cháo shí​qī céng shì yī gè zhū​hóu​guó.

   The State of Wei was a vassal state during the Zhou Dynasty.

   Source: Dong Chinese Dictionary

5. 郑国是周朝时期的一个重要诸侯国。

   Zhèng​guó shì Zhōu​cháo shí​qī de yī gè zhòng​yào zhū​hóu​guó.

   The State of Zheng was an important vassal state during the Zhou Dynasty.

   Source: Dong Chinese Dictionary

6. 曹国是周代的一个诸侯国，后来被宋国兼并。

   Cáo​guó shì Zhōu​dài de yī gè zhū​hóu​guó, hòu​lái bèi Sòng​guó jiān​bìng.

   Cao was a vassal state during the Zhou Dynasty, later annexed by the State of Song.

   Source: Dong Chinese Dictionary