How do stress, pitch, tone, and intonation function as suprasegmental features?

In phonetics, suprasegmental features are speech elements that extend over syllables, words, or phrases, rather than being limited to individual consonants or vowels. These features are defined by their relative values within an utterance, as absolute values are not linguistically significant.12

• Stress (Accent): Involves increased respiratory and laryngeal activity, resulting in greater air pressure and pitch changes. It can serve a grammatical function, such as distinguishing nouns from verbs (e.g., an insult vs. to insult), or provide contrastive emphasis.2
• Pitch: Refers to the frequency of voice vibration. It is the fundamental component of both tone and intonation.32
• Tone: Uses pitch modulation to differentiate the meaning of individual words. For example, in Mandarin Chinese, the same syllable can have entirely different meanings depending on the pitch contour applied to it.321
• Intonation: Describes the melodic pattern of an utterance. It functions at the sentence level to convey expressive meaning (such as emotion) or grammatical information, such as distinguishing a statement from a question.32

Together, these features provide essential layers of meaning beyond the basic segmental content of speech.12