be my guest

1.
British EnglishAmerican Englishgeneralinformalneutralpolite
- Used to give permission or encourage someone to do something; 'feel free' or 'go ahead'.
- Used to offer assent in a courteous or nonchalant way, sometimes with ironic or sarcastic tone.
2.
British EnglishAmerican Englishgeneralneutral
- To be an invited guest in someone's home or at an event; to be hosted by another person for a specified time or occasion.

Examples:

EN: Son of Maria Obal, be my guest.
ES: "Vaya, el hijo de María Obal...
EN: And tonight you will be my guest.
ES: Y esta tarde sereis mi apreciado invitado.
EN: I'd be tickled to death if you'd be my guest some night when I get back.
ES: Me encantaría invitarlo a cenar cuando regrese.
EN: But be my guest, have a good look.
ES: Pero sean bienvenidos, busquen bien.
EN: Miss Landers happens to be my guest.
ES: La Srta. Landers es mi invitada.
EN: I provided Ms. Brent with this gown so she'd be my guest.
ES: Le compré a la Sra. Brent ese vestido para que fuera mi invitada.
EN: You could be my guest over the weekend, and we could go through his papers together.
ES: Podría ser mi invitado este fin de semana. Y podríamos revisar sus papeles juntos.
EN: I wanted you to be my guest.
ES: Y quise que fuera mi invitado.
EN: Oh, no, no, no, you be my guest.
ES: Oh, no, invito yo.
EN: You shall be my guest and kill him.
ES: Será mi invitado.
EN: It was understood you were to be my guest, you know.
ES: Acordamos que serías mi invitado.
EN: You'll be my guest tonight.
ES: Esta noche serás mi invitada.
EN: You'll be my guest for tonight, you know, reception.
ES: Será mi invitado esta noche, ya sabe, la recepción.
EN: Then you'll be my guest for the evening.
ES: ¡Sea mi invitada!
EN: I sent for you to be my guest.
ES: Yo quiero que sea mi invitado.