How to justify in an essay pls help me

You justify by giving further reasoning and explanation to your answer. This can be through explaining your own thinking (If you think A how did you get to this conclusion) Or you can provide evidence for your claim (if you claim that cars are dangerous and bad for society provide examples of crashes/deaths due to cars). Usually providing a bit of both is best. If you need further help just comment. I could probably give a better answer with some context/what you have so far.

After she won a small part in a local production of The King and I, her popularity grew quickly. 
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