sue – v. take legal action against a person or organization

complain – v. express unhappiness about something

tangible – adj. something that is real and can be seen

resort to – v. do something that you do not want to do because you cannot find any other way of completing it

determined – adj. having a very strong desire to do something

emission – n. the act of producing or sending out something (such as energy or gas) from a source

mandatory – n. required to do