Para pedir perdón, I'm terribly sorry e I'm really sorry son fuertes y cálidas. I apologize es un poco más formal.
Disculparse
I'm terribly sorry — I'm terribly sorry for the wait.
I apologize — I apologize for the trouble.
I'm really sorry — I'm really sorry about this.
Pruébalo: Amina: There is a problem with my room. Hiroshi: ___ What is wrong? Hiroshi works at the hotel and wants to apologize. Which fits? (I'm terribly sorry. / Excuse me, but / I'm not happy with) Respuesta: I'm terribly sorry. — I'm terribly sorry es una disculpa, lo cual encaja con la respuesta de Hiroshi. Excuse me, but e I'm not happy with se usan para quejarse, así que ninguno de los dos se disculpa.
Quejarse con cortesía
Para quejarte de forma cortés, empieza con Excuse me, but, y luego di There's a problem with o I'm not happy with antes de aquello que está mal.
Excuse me, but — Excuse me, but this is cold.
There's a problem with — There's a problem with my room.
I'm not happy with — I'm not happy with the noise.
Pruébalo: Sofia: How is everything in your room? Diego: ___ the noise. I can't sleep. Diego wants to complain politely about the noise. Which fits? (I'm not happy with / I apologize / I'm really sorry) Respuesta: I'm not happy with — I'm not happy with introduce una queja cortés, lo cual encaja. I apologize e I'm really sorry son disculpas, así que ninguno de los dos se queja.