"Great bravery", can mean lots of things. One of its synonyms is heroism. But what exactly is heroism? Most people would say,"A hero is someone who has given his or her life to something bigger than oneself...." but is this actually true? Is a hero actually someone who has given his or her life to something bigger than oneself? Let's take Harriett Tubman for instance. She risked her life to guide slaves to the north. Take John F. Kennedy for instance, he saved his crew from bombing.
You can use this as a lead try to finish the rest. If you like it ask me to do more.
