Listening, speaking, reading, and writing are the four basic language skills human beings are respectively exposed to from early birth. The development of each of these skills is piecemeal and, at the same time, wide-ranging due to many different natural, environmental and institutional factors. Myriad theories and methodologies have already been proposed, and countless descriptive and experimental studies have been conducted in the past seventy years to foster and facilitate the process of such a development for each skill in both first and second language acquisition. Yet, there is a long way researchers have to pave to be able to articulate an all-inclusive statement which can cover all corners of this seemingly unbounded issue. This is definitely due to the very nature of language learning and teaching, with their vast, varied and infinite divisions which resist irrefutable conclusion. This book presents the authors' efforts to cut down such a pebbly path.