The nucleus

The last stressed syllable of the intonation pattern on which the pitch movement changes is called the nucleus. The nucleus is usually of the highest importance; it is on this syllable that the whole pitch pattern centres.

Different linguists single out different number and different types of nuclear tones. The commonly recognized nuclear tones are 1) the Low (Medium) Fall, 2) the Low (Medium) Rise, 3) the High Fall, 4) the High (Medium) Rise, 5) the Rise-Fall, 6) the Fall-Rise, 7) the Level Tone. Some scholars also distinguish the Rise-Fall-Rise.

The Tail: Post nuclear unstressed or partially stressed syllables are called the tail.