Tone units

A TONE UNIT is the “basic unit of intonation” .It is also known as an "Intonational phrase", "speech unit" or "tone group" 

A tone unit is a unit generally greater in size than the syllable.

Most tone units are of a type that we call “simple”. Each simple tone unit has one and only one “tonic syllable” which is and obligatory component of the tone unit. 

Each tone unit has four components:

The tonic syllable

It is the syllable on which the mayor pitch movement begins. It is a syllable which carries a tone. It has a high degree of prominence and it not only carries the tone, but also a type of stress that will be called tonic stress.  

The head

It is all of that part of a tone unit that extends from the first stress syllable up to (but not including) the tonic syllable. If there is no stressed syllable before the tonic syllable, there cannot be a head.

The pre – head

It is composed of all the unstressed syllables in a tone unit preceding the first stressed syllable. It is found in two main environments

    a. When there is no head. I.e. no stressed syllable preceding the tonic syllable.

    b. When there is a head

The tail

 Any syllables between the tonic syllable and the end of the tone unit.

• When we analyse longer stretches of speech, it is necessary to mark the places where tone unit boundaries occur – that is where one tone unit ends and another begins, or when a tone unit ends and is followed by a pause, or where a tone unit begins following a pause. 

• Tone units are sometimes separated by silent pauses and sometimes not. Pause type boundaries can be marked by double vertical lines and non-pause boundaries with a single vertical line. 

• Although there are no rules about how we divide speech into nits, some words are more likely to go together than others in order to help make sense of the message.

                 //we stuck a picture//of an elepehant//

• Sometimes the division of speech units can make a difference in meaning

              //we were rather naughty// once// we stuck a picture// of an elephant//
             //we were rather naughty once// we stuck a picture// of an elephant//

• When we want to emphasise words in order to draw particular attention to them, we can put them into very short speech units.

Within a speech unit, some words are made prominent and other non-prominent. Words are made prominent in order to emphasise them because they carry important or interesting information.

Non-prominent words are not so important. They may repeat information that has already been given or give information that is already understood. 

Some speech units have more than one prominent word in them. Each prominent word is emphasise because it carries important information. The last prominent word is where the main falling or rising tone starts.