How does the use of nonverbal communication, such as making eye contact, a speaker connect with the audience?

Eye contact so the speaker seems more human and relatable.

Explanation:

When you are making a speech, making direct eye contact with the  people listening to you help you establishing a relationship with, it makes them feel like you are talking to them personally.

Gesture supporting your speech can help underline some points and make the audience feeling closer to you.  That the same for smiling and other nonverbal communication.

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