The human voice consists of sound made by a person using the

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The human voice consists of sound made by a person using the vocal folds for talking, singing, laughing, screaming or crying. The vocal folds, in combination with the teeth, the tongue, and the lips, are capable of producing highly intricate arrays of sound; vast differences in meaning can often be achieved through highly subtle manipulation of the sounds produced (especially in the expression of language). These differences can be in the pronunciation of the individual noises, or in the overall tone in which they are uttered.

The tone of voice may suggest that a sentence is a question, even if grammatically it is not, and can display emotions such as anger, surprise, or happiness. In a request, the tone can reveal how much the speaker wants something, and whether that speaker is asking a favor or giving more of an order. The tone of saying, for example, "I am sorry" can change the phrase's meaning dramatically: it may vary from seeming a sincere request for forgiveness to implying something like, "I have the right to do this even if you do not like it".

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