What does it mean to know howto use a language? An essay on the theoretical basis of language testing

Language testing and linguistic theory must both try to define language knowledge and use. There are three main approaches. The Structural claim, which assumes that knowledge can take the form of a grammar or structural description of the language, forms the basis of discrete point tests. The Functional approach assumes that the nature of language knowledge is best captured by listing the various uses to which it can be put; it is embodied in the communicative competence model, the notional-functional curriculum, and the interest in teaching and testing pragmatics. The General Proficiency claim is based on the notion that individuals vary in possessing measurable amounts of an indivisible body of knowledge. It underlies arguments for a general factor underlying batteries of tests or for the trait measured by certain test methods like the cloze. The theoretical strengths and weaknesses of these approaches and the impossibility of showing that any one is completely correct forces us to consider all three as basic to testing. Anybody who knows a second language must be assumed to have all three kinds of knowledge, so that we can only achieve the full picture of language proficiency if we use many different measuring method and know what trait is being tapped by each test.