Please make yourself at home请不要客气

今天的几个句子是有关礼貌的：1.Have a seat, and make yourself at home. 请坐。请不要客气。2.There is plenty for everyone, so help yourself! 这儿有很多，足够每个人吃，所以不要客气！3.If you want to borrow the car, be my guest. 如果你要借那辆车，请不要客气。