enter or assume a certain state or condition; "He became annoyed when he heard the bad news"; "It must be getting more serious"; "her face went red with anger"; "She went into ecstasy"; "Get going!"
come into existence; "What becomes has duration"
undergo a change or development; "The water turned into ice"; "Her former friend became her worst enemy"; "He turned traitor"
work that you are obliged to perform for moral or legal reasons; "the duties of the job"
the social force that binds you to the courses of action demanded by that force; "we must instill a sense of duty in our children"; "every right implies a responsibility; every opportunity, an obligation; every possession, a duty"- John D.Rockefeller Jr
a government tax on imports or exports; "they signed a treaty to lower duties on trade between their countries"