VOCABULARY MASTERYAS A FACTOR THAT INFLUENCE ABILITY TO WRITE EXPOSITION TEXT

The research is motivated by the following cases. First, students vocabulary deficiencies in writing so have difficulty in presenting ideas into a text. Second, the students do not understand about exposition text. Third, students difficult to differentiate exposition text with other text. Fourth, students difficult to develop ideas in writing, so that the resulting of their text is not in accordance with the idea that their think. Fifth, students difficult to write cohesion and coherence paragraphs. This type of this research is quantitative with correlation method. The population in this research is students of class X SMA Negeri 1 2x11 Enam Lingkung Padang Pariaman District with 281 students. In this research, the sampling technique is proportional random sampling with 27 students. In this research, there are two variables, are independent variable and the dependent variable. The independent variables are vocabulary mastery (X) and the dependent variable is the exposition text writing skills (Y). Conclusions of this research are as follows. First, vocabulary mastery of class X SMA Negeri 1 2x11 Enam Lingkung Padang Pariaman District with an average value of 73,17 which are in the category Lebih dari Cukup. Second, the writing skills exposition text of class X SMA Negeri 1 2x11 Enam Lingkung Padang Pariaman District with an average value of 70,98 which are in the category Lebih dari Cukup. Third, there is a relationship between the vocabulary mastery with writing skill exposition text of class X SMA Negeri 1 2x11 Enam Lingkung Padang Pariaman District because tcount>ttable. The conclusion of this research is the vocabulary mastery is a factors that influence significantly the writing ability exposition text of class X SMA Negeri 1 2x11 Enam Lingkung Padang Pariaman District.