We’ve now seen that the field of linguistics approaches the study of language from a scientific point of view. As linguists, we seek to make systematic, descriptive observations about human language behaviour. From these empirical observations, linguists have learned that every speaker of every human language has a mental grammar. And the mental grammar of every language includes systematic principles for how sounds (or hand signs, in a signed language) are made, for how these sounds or signs are organized into words, for how words and smaller pieces of words are combined to form phrases and sentences, and for how we assign meaning to words and sentences. When we speak our language, we use our mental grammar to generate new phrases and sentences, and the people who listen to us use their mental grammar to understand us.