Answer:
Barak Obama: He has such a free spirit & comfortability that draws the audience intently. 
Nelson Mandela: from his speech, you'll see why he has such a potentiality to be a great leader. 
Greta Thunberg: in spite of having an autism disorder, she is such a great speaker. She is down to the point, less speaking & clear cut which astonishes the audience. 
Emma Watson: she speaks with an aura of confidence & has such a gravity which is mesmerising. 
Kim Namjoon: though English is not his native language, he is really fluent in it & above all, he can make the audience follow him. 
From all these above personalities, I get influence to become a better speaker. 
Step-by-step explanation:
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