Four areas of language arts, speaking, listening, reading and writing, are interactive and integrative. And also they are intentional and purposeful. The acquisition and development of language ability is based on the hypotheses of the imitation, the innatism and the interaction. However, the present persuasive theory is the interative hypothesis. The language is the house and the mediator of thinking. And then the thinking by language is developed through the language use activities. There are the meta-cognitive method, the componential approach, and the heuristic approach in the language teaching methods to develop the thinking ability. The conceptual inquiry method and the empirical research method are used in the researches of language arts area. (speech communication) The research on speech communication education is classified, depending on what is studied, into two: a study on the participants of speech communication and a study on the phenomenon of teaching-learning in speech communication. The 'study on the participants of speech communication' is a study on the participants, message, communication media and discourse situation, which are the components of communication through spoken language. The 'study on the phenomenon of teaching-learning of speech communication' is a study on the goal, contents and assessment in the field of speech communication education. The ultimate goal of these two studies is an improvement of teaching and learning in speech communication. Recently, These studies are influenced by the transactional theory, cognitive views of speech communication education and dialogue analysis study. In the future, fundamental researches on diverse subjects in the field of speech communication teaching-learning are essential for the development of speech communication education. Furthermore, we need to explore the contents and method of speech communication teaching-learning based on the dialogue pattern and objective. The ways of research on the speech communication education must be diversified depending on its subjects and objectives. Besides, an active research on the listening education and a study reflecting or adopted from theories of other related fields should also be followed. (reading) In order to know the current tendency of research in the field of reading education, the concept of reading was examined and the constraints of reading ability were discussed. Reading can be seen as the process of constructing meaning [micro reading] and the purposeful action related to gain diverse information, knowledge, and wisdom and cultivate personality and self-identification [macro reading]. Considering the comprehension process and the nature of reading, reading ability is composed of a variety of sub-abilities: decoding ability, recognition ability, experience and prior knowledge-utilizing ability, inferencing ability, knowledge related to text organization, literal, inferential, critical, and creative comprehension ability, reading strategy-command ability, perceptibility, physiological ability, language competence, intellect, and affection. Under the influence of socio-constructivism, the approach to reading education shifts from skill-based reading teaching to strategy-based teaching and to activity-based teaching. Early researches of text in reading education depended on rhetoric, but recent researches are much grounded on text linguistic. On the side of research theme, the concept of reading skills is treated in early, but the development of reading strategies or activities is mainly discussed in recent. In the future, it calls for further studies related to macro reading and discussions about the principle of choosing the materials and the standard for judgment of text difficulty. It remains to be studied in the development of the detailed and elaborated knowledges about text, and then, in translating them into the content of reading education. Also it needs exploration of content area reading across the curriculum. (writing) This chapter investigate 'writing ability' through the analyses of three writing theories: formalism writing theory, which offer the application of rule grammars and rhetoric conventions, congnitivism, which offer the strategic use of meaning formation and problem solving, and socio-congnitivism, which provide for awareness of audience and transaction of audience and writer. Then until now the trends of 'researches on teaching of writing' are categorized writing process-based researches, genre-based researches, researches on combining reading and writing, researches on writing elements, researches by microscopic method. In addition to, some researches recently give attention to university writing and academic writing(technical writing). Future researches aim at the development of writing ability, connection reading and writing, technical concepts and terms of writing and writing education, relationship to creative writing in literature area, writing across the curriculum.