In American's eyes, however, if it is not said, it is considered rude. Whether it's your boss, colleague, stranger on the road that did something nice for you, a friend or American family member, not saying thank you for something someone else has done for you could make them think you feel entitled (maybe known as 'ego' in Kerala). So, how do we say thank you? We can simply say "thank you" or follow some tips from this post on saying thank you in emails or from the video below on how to respond to thank you in live conversation.
How to respond to thank you
How to impress Americans professionally
Mistakes made by enthusiastic Indians in global teams