Taboo is something that is strictly forbidden to do both utterances and actions based on beliefs and this almost exists in all societies. Maybe for us ordinary but not for them. Here are the things that need to be avoided when in the UK or when interacting with the English. Meanwhile, you can go to Trinity college leeds if you feel like to take the English exam for your Visa to the UK.
ASK ABOUT SALARY
In other cultures, it is probably normal for us to ask about their salary. But in the UK, people there will not be comfortable to tell their income to pay for life. If you ask about it they will feel you are entering their private area too soon.
In the culture of the people there, they are very guarding and respecting the privacy of each and ensure that each privacy is maintained. Asking about salary should not be made as a first topic especially when new meet. Usually, they will not answer that question. Yet another thing if you are their close friends or family.
SPITTING IN PUBLIC PLACES
It is clear that spitting is something that is disgusting. Spitting in public places is rarely found in the UK. In England, they consider spitting is antisocial, dirty, disgusting and can not be accepted. Because it is possible that the saliva carries a virus or people will accidentally put in their shoes and take it home. Same thing with cleaning their nose disgusted about this. Use the tissue if you need it.