Diana Prince: You're a man...
Steve Trevor: Yeah... I mean... do I not look like one?
Steve Trevor: Welcome to jolly old London.
Diana Prince: It's hideous!
Steve Trevor: Yeah, it's not for everybody.
Steve Trevor: Have you never met a man before? What about your father?
Diana Prince: I had no father. My mother sculpted me from clay and I was brought to life by Zeus.
Steve Trevor: Well, that's neat.
Charlie: May we get what we want...
Steve Trevor: ...and may we get what we need.
Sameer: But may we never get what we deserve.
Diana Prince: I am Diana, Princess of...
Steve Trevor: Prince! Diana Prince.
Steve Trevor: I can't let you do this.
Diana Prince: What I do is not up to you.
Queen Hippolyta: Be careful in the world of men, Diana. They do not deserve you. You have been my greatest love. Today, you are my greatest sorrow.
Steve Trevor: I can save today. You can save the world.
Diana Prince: I can not stand by while innocent lives are lost.
Diana Prince: I will fight, for those who can not fight for themselves.
Etta Candy: I'm Steve Trevor's secretary.
Diana Prince: What is a secretary?
Etta Candy: I go where he tells me to go, I do what he tells me to do.
Diana Prince: Where we come from, that's called slavery.
Etta Candy: I like her.
Queen Hippolyta: I used to want to save the world, this beautiful place. But the closer you get, the more you see the great darkness within. I learnt this the hard way, a long, long time ago.
Diana Prince: It's about what you believe. And I believe in love. Only love will truly save the world.
Answer: For the majority of the movie, Diana believes the sword to be the only weapon capable of killing Ares. She doesn't realise until she fights him that the sword is just an ordinary weapon and thus, useless against a god. She carries the shield because it is useful. She uses it in combat most prominently to block gunfire.
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