Have to do with

 Help yourself to...
请随便吃······

用法透视
招待客人时，我们经常对他们说"不要客气，请随便吃......"，学了这个句型以后，就不要再说"please eat..."。

支持范例
1. Make yourself at home. Help yourself to some fish.
不要客气。请随便吃点鱼。
2. Help yourself to the refrigerator.
请随便在冰箱里拿。
3. Help yourself to some steak. I made it especially for you.
请吃点牛排。我特意为你做的。

会话记忆
A: Thanks for inviting me over for dinner this evening.
谢谢你今晚请我来吃饭。
B: You're welcome.
不客气。
A: It looks delicious.
看起来很好吃。
B: Well here. Help yourself to some shrimp. It's fresh.
来，请吃虾，是新鲜的