Read the text below. A Basic Model of Language Learning Learning an additional language necessarily involves at least five elements, or to put it another way, any explanatory model of language learning must take into account at least the following five elements: To start off, there must be _____________, the person learning the language. No language learning will take place if the learner is not exposed to ____________, some form of the language being learned, and one of many constituents of _____________. In the process of learning the language, a systematic representation of that knowledge, _____________, develops inside the learner's head. Learning is evident in ____________, a display of the learner's ability in the language (Barkhuizen, Gary, in Social influences in Language Learning). Observing the context above, choose the best option that completes the paragraph in the correct order.