Talk about things which are /aren´t good manners in your country if you are staying with someone as a guest, and what you think is the right thing to do.
I think is very rude to criticize the food if you are in somebody´s house, even if it´s your family.
I think is bad mannners to arrive more than ten minutes late for lunch or dinner when you are invited to somebody´s house.
I think is bad manners to answer or send a text or message when you are having a meal with friends in a restaurant.
I think is bad manners to post a private message or conversation on an internet site.
I think is bad manners to post an embarrassing photo or video clip of a friend without asking their permission.

