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Speech Rules!

Development of speech

A staggering amount of growth and change occurs within the first five years of a child’s life. An important  change is the development of speech. If you considered all the physical, psychological and social factors necessary to achieve speech, you might wonder how children ever learn to speak at all. However, a comparison between typically developing children shows that their pattern of speech development rarely differs. They also achieve speech easily.

Early speech development

Up to the age of two months babies cry vigorously when uncomfortable or hungry. They coo when they are content and vocalize in response to seeing their mother. As they grow, so the sounds they make become more recognizable as the same sounds that adults use. At six months of age, children are babbling and beginning to string together double syllables such as ‘ah-ah’ and ‘muh-muh’. At around nine months these strings become longer. Children take pleasure in vocalizing sequences of sounds such as ‘agaga’ and ‘adaba’. Twelve to 15 months is the ‘One Word Stage’. This is when children speak up to 10 recognizable single words without prompting. They will, however, be able to understand many more than this and can follow simple instructions such as, ‘show me the ball’, and ‘give it to daddy’.

The child’s vocabulary now develops at an astonishing rate. It is so rapid that at two years they will speak well over 200 words and understand many more. This is the ‘Two Word Stage’. This is exactly as its name suggests – the stringing together of two words to form infant sentences like, ‘ball gone’, and ‘mammy go’. By the time a child is three years they will be able to recite a number of nursery rhymes, count to ten, give their name, and tell you if they are a boy or a girl. They will also continuously ask questions that begin with ‘what’, ‘where’, and ‘who’ – they’ll be a proper little chatterbox!

Throughout all this development parents and carers develop insights about just what it is that children are trying to say. Suppose three-year-old Amanda points to the kitchen table and says, ‘want pup’. You would probably pass her a cup. If she then pointed out the window and said, ‘cac!’ you might reply, ‘Yes, Amanda, it’s a cat!’ You probably wouldn’t give what she said a second thought. However, if you did concentrate on how she is pronouncing particular words you would conclude that she is not saying them properly.

If you listened very carefully to what Amanda was saying, and you knew how to scientifically record her pronunciations, you’d discover that she was remarkably consistent at making mistakes. In fact, she would make the same mistakes over and over again. It’s as if she were following rules which tell her which mistakes to make and when. Also, if you recorded the speech of thousands of other children, you’d come to the startling realization that everyone of them was making the same mistakes as Amanda. Consequently, you’d have to conclude that they are also using the same rules to govern their mistakes.

Phonological simplifying processes

Speech scientists have identified dozens of rules called ‘phonological simplifying processes’. What this means is that the child, because of their age, has not developed sufficiently to co-ordinate the movements of their lips, mouth and tongue in order to make certain sounds in words. Basically, it’s just too difficult for them at present. So they make other sounds which are simpler to produce. But children don’t just pick any sound at random. There are certain rules, which are pre-programmed in the brain, which ‘tell’ the child which sound or sounds to use. Let’s take a look at some of these rules.


The child who says, ‘bo-bo’ for ‘bottle’ or ‘pu-pu’ for ‘pudding’ is reduplicating. They are repeating the first syllable. Basically, it’s simpler to say the same thing twice than it is to alter the tongue and mouth position to say two different things. Another example is ‘mi-mi’ for ‘mirror’. Reduplication is used typically from two to two and a half years of age.

Consonant harmony

Vowels are anything like ‘a, e, i, o, u’ and consonants are basically everything else. Speech scientists don’t like to describe vowels quite like this but, for our purposes, it illustrates the point. Sometimes words that are made up of a consonant-vowel-consonant sequence, such as ‘dog’ or ‘cat’, are too complicated for a young child to say. From the age of two to three years, they may use consonant harmony. With this process, the first consonant may become the same as the last consonant, as when ‘dog’ becomes ‘gog’ or ‘pot’ becomes ‘tot’. Alternatively, the last consonant may become the same as the first, as when ‘cat’ becomes ‘cac’ and ‘pan’ becomes ‘pap’. The consonants are said to harmonize or, put simply, they become the same. This may seem complicated but the child is not aware of the rules they apply, nature does it all for them.


Sometimes it can be easier to miss out particular sounds. This is known as deletion. Typically, from two to four years a child might leave off consonants which appear at the ends of words. For example, ‘bed’ becomes ‘be-‘, ‘top’ becomes ‘to-‘, and ‘man’ becomes ‘ma-‘. In some cases, whole syllables may be left out such as ‘banana’ becoming ‘bana’, ‘pyjamas’ becoming ‘darmud’, and ‘potato’ becoming ‘tato’.

There are many more examples, but I hope that you can see that most of the ‘mistakes’ children make are not really mistakes at all. Speech scientists are able to analyze a child’s speech and then predict what they will say when asked, for example, to name a familiar object. Most children are still using some phonological simplifying processes up to the age of five years, and some beyond this. It is also not unusual for a child to be as old as six or six and a half years before they are capable of saying all the speech sounds an adult would use.

The fact that children do use rules which are built into them before birth confirms for me just how special and wonderful children really are.

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