2 sentences

1. 既然你来了，就请留下来吃顿家常便饭吧。

   jì​rán nǐ lái le, jiù qǐng liú xià​lai chī dùn jiā​cháng​biàn​fàn ba.

   Since you're here, please stay for a simple home-cooked meal.

   Source: Dong Chinese Dictionary

2. 由于工作繁忙，加班对他来说已经是家常便饭了。

   yóu​yú gōng​zuò fán​máng, jiā​bān duì tā lái shuō yǐ​jīng shì jiā​cháng​biàn​fàn le.

   Because he's so busy, working overtime has become a routine for him.

   Source: Dong Chinese Dictionary