Over on Instagram (@lucypollardtherapies), I've been sharing lots of information about understanding language. One area a speech and language therapist looks at when assessing this is Key Word Understanding. So I thought I'd explain a little more here about what this is, how you assess it, and why it matters.
Key words are words that must be understood for someone to make sense of an instruction. That explanation is not very easy to understand in itself! Let's take an example. Think about this sentence, which I may have uttered many times to my own children:
"Put your hat on your head."
Quite a lot of words! 6 in fact! How many of these are Key Words? Imagine the child is by the front door; coat and boots on. An array of accessories are in front of him - hats, gloves, scarves etc. In order to make sense of the instruction, he must understand the word hat. So this is a Key Word. What about the other words? You might think that 'put' is a Key Word, because I'm telling him what he needs to do. But what else are you going to do with hats on heads? If I took the word 'put' away, would the child still be able to follow the instruction? "Hat on your head" still carries the same information. So 'put' is not a Key Word in this sentence. What about if I changed the verb?
"Throw your hat on your head."
Ah, that's different. Now the child has to understand the word throw to make sense of the instruction. Now the sentence has 2 Key Words. "Hold on! What about 'head'?" you very rightly ask. This sounds like it must be a Key Word. But again, where else are you going to put your hat? Can we take this word away? "Put your hat on" still carries the same information, and will almost certainly lead to the same outcome (unless the child in question is particularly contrary!). So 'head' is not a Key Word in this sentence. What about if we change it?
"Put your hat on your hands."
A bit weird, but now the child has to understand the words hat and hands to make sense of the instruction. So this sentence also has 2 Key Words. "Ahhh, but what about the word 'on'? Surely this is a Key Word," some clever clogs points out. This is another sneaky one. Sounds like a Key Word, but putting hats on heads is the default position, so you can't really be sure that the child understands the concept of 'on' if they follow this instruction. Compare this to:
"Put your hat behind your head."
Now the child has to understand hat, behind and head to make sense of this instruction. So this has 3 Key Words.
Let's try some more:
"Put your hat on the table." (2 Key Words)
"Put your hat under the table." (3 Key Words)
"Put Maya's hat under the table." (4 Key Words)
"Put your brother's red hat in the bag." (5 Key Words)
By now this poor child must be very confused, so we'll leave him to put his hat on in peace. Key Word Understanding is an important marker of language understanding (also known as receptive language), especially among younger children. Organisations such as the Derbyshire Language Scheme and Elklan have created in-depth programmes to support children's skills in this area. They call Key Words 'Information Carrying Words'. Have a look at their websites if you would like more information.
Why does all this matter? For one thing, it's useful to know that there is a difference between length of utterance and number of Key Words. A child might appear to be understanding long sentences, but if that sentence doesn't contain many Key Words, then that might be masking a difficulty with understanding language. I'll finish off with one final example. The child is by the front door, coat on, boots on. My hat is already on my head. I hand him his hat and say "Put your hat on your head." How many Key Words in the sentence now? Precisely zero. I could have said nothing, and the likelihood is he would have inferred from my actions, and from the context, what it is that I wanted him to do. Children are incredibly talented at inferring meaning from observing the actions of those around them. Children with language delays are especially good at doing this. A child who seems to be following verbal instructions well at times may be masking their difficulties by using this sophisticated skill. And THAT is why key words are important.