5 sentences

1. 他坐得非常端正。

   tā zuò de fēi​cháng duān​zhèng.

   He sat very upright.

   Source: Dong Chinese Dictionary

2. 那个女孩五官端正，非常漂亮。

   nà​ge nǚ​hái wǔ​guān duān​zhèng, fēi​cháng piào​liang.

   That girl has well-proportioned features and is very beautiful.

   Source: Dong Chinese Dictionary

3. 这小伙子长得好个人才，五官非常端正。

   zhè xiǎo​huǒ​zi zhǎng de hǎo gè rén​cái, wǔ​guān fēi​cháng duān​zhèng.

   This young man is quite handsome, with very regular features.

   Source: Dong Chinese Dictionary

4. 我们要端正学习态度。

   wǒ​men yào duān​zhèng xué​xí tài​du.

   We must correct our attitude toward learning.

   Source: Dong Chinese Dictionary

5. 他品行端正，深受老师和同学们的喜爱。

   tā pǐn​xíng duān​zhèng, shēn shòu lǎo​shī hé tóng​xué men de xǐ'ài.

   He has upright conduct and is deeply loved by his teachers and classmates.

   Source: Dong Chinese Dictionary