In general, words used for academic are slightly different from these of daily life. Japanese is not its exception. There are some useful Japanese phrases for living in Japan. It is better for international students in Japan to know them.
“Suimasen” is one of the most such used Japanese phrases because it has many meanings. Firstly, it means “Excuse, me” When you talk to others, it can be used. Secondly, it means “I’m sorry”. It sounds very casual apologizing. Thirdly, it means “Hello?” when you call someone in a shop. Fourthly, it means “Thank you”. It also sounds casual thankfulness. Fifthly, it means “excuse me, but”. It is used before a request for. It makes the request more politeness.
As previously noted, “Suimasen” is so useful phrases in many occasion. However, as you might feel, it sometimes sounds casual and easy. Therefore, it isn’t adequate in some formal or serious occasions. Still, this word is used by many people in many occasions every day.