Abstract :
The objective of this research was to get empirical evidence about the effect of
conversation class program on the student?s Vocabulary mastery and to identify the student?s
achievement in learning vocabulary through Comparative Adjective method. This research used
quantitative method. The sample of this research was the first grade students of SMAS Islam Nur
Ihsan, with the total number 25 students from each class The research conducted in two different
classes with comparative adjective was employed in an experimental class and other technique
was employed in a controlled class. The data were collected through the achievement of pre-test
and post-test from two classes. The result showed that teaching vocabulary by using comparative
adjective was more effective than using conversation method. Comparative adjective has served
a positive influence. So, it can be conclude that comparative adjective method has positive effect
to the first grade students of SMAS Nur Ihsan in teaching vocabulary mastery.