4 sentences

1. 你今天怎么这么勤快？

   nǐ jīn​tiān zěn​me zhè​me qín​kuài?

   Why are you working so hard today?

   Source: OpenSubtitles

2. 那个打工仔很勤快。

   nà gè dǎ​gōng zǎi hěn qín​kuài.

   That young migrant worker is very hardworking.

   Source: Dong Chinese Dictionary

3. 她干活勤快吗？

   tā gàn​huó qín​kuài ma?

   Is she hardworking?

   Source: OpenSubtitles

4. 那个年轻的服务生在餐厅里工作非常勤快。

   nà gè nián​qīng de fú​wù​shēng zài cān​tīng lǐ gōng​zuò fēi​cháng qín​kuài.

   That young waiter works very diligently in the restaurant.

   Source: Dong Chinese Dictionary