4 sentences

1. 孟子是战国时期的思想家。

   Mèng zǐ shì Zhàn​guó shí​qī de sī​xiǎng​jiā.

   Mencius was a thinker during the Warring States period.

   Source: Dong Chinese Dictionary

2. 卡尔·马克思是伟大的思想家。

   Kǎ'ěr · Mǎ​kè​sī shì wěi​dà de sī​xiǎng​jiā.

   Karl Marx was a great thinker.

   Source: Dong Chinese Dictionary

3. 庄子是中国古代著名的思想家。

   Zhuāng​zǐ shì Zhōng​guó gǔ​dài zhù​míng de sī​xiǎng​jiā.

   Zhuangzi was a famous philosopher in ancient China.

   Source: Dong Chinese Dictionary

4. 实现小康社会是许多古代思想家的毕生追求。

   shí​xiàn Xiǎo​kāng shè​huì shì xǔ​duō gǔ​dài sī​xiǎng​jiā de bì​shēng zhuī​qiú.

   Achieving a moderately prosperous society was the lifelong pursuit of many ancient thinkers.

   Source: Dong Chinese Dictionary