2 sentences for 勤 (qín — frequent)

1. 他最近往图书馆跑得很勤。

   tā zuì​jìn wǎng tú​shū​guǎn pǎo de hěn qín.

   He has been going to the library quite frequently lately.

   Source: Dong Chinese Dictionary

2. 他们两家是表亲，所以走动得很勤。

   tā​men liǎng jiā shì biǎo​qīn, suǒ​yǐ zǒu​dòng de hěn qín.

   The two families are cousins, so they visit each other frequently.

   Source: Dong Chinese Dictionary