Origin of Language

I think language comes from an innate desire to express yourself and your desires. Think back to when you were a tiny toddler just learning to speak. What is it that made you speak? You wanted something or were unhappy with the way things were going. You wanted to express these desires and thoughts, you started with pointing and crying and slowly evolved to the word no! and naming objects and people. When your thoughts and ideas became more complex you needed more complex structures to express them. You learned to speak in short sentences and later on in complex sentence structures. 

The impact this has on L2 teaching is that you need to create the desire and need to learn. Students need to feel the same need to express their thoughts and feelings in the second language as they felt in their mother tongue. A teacher needs to create the circumstances in which the desire to express and the need to do it in another language converge.