Achange in facial expression, a pause, an altered vocal pitch or speaking rate, or a movement all may indicate a

Nonverbal transition

Explanation:

Nonverbal transition involves using nonverbal communication techniques to pass across a message effectively to an audience. They are often employed by people who engage in public speaking to ensure a good flow of conversation.  Nonverbal transition elements, such as a change I facial expression, a pause, an altered vocal pitch or speaking rate etc., are used alone or mixed together by a speaker to attract and sustain the interest and attention of the audience.

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