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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
