If you are in doubt about how to address someone, you should first use the formal name and wait for them to suggest that you use the first name. As a rule, gifts are given to relatives and close friends. They are sometimes given to people with whom one has a casual but friendly relationship, such as a host or hostess, but it is not necessary or even common for gifts to be given to such people. Gifts are not usually given to teachers or others who hold official positions. The offering of gifts in these situations is sometimes interpreted as a possibly improper effort to gain favorable treatment from that person.
Various gestures are automatic and vary from culture to culture.
While in other countries, burping may be seen as a complement to the cook. If a person's words and gestures do not seem to match, it would be wise to ask the individual. Students will, however, dress more formally for certain class presentations. Casual dress is also appropriate for visits in people's homes, shopping or movie theatres. You might dress more formally for a special dinner or a special event at the University.