This book reveals that speaking performance of one is mainly related to his/her knowledge of the words. The researcher himself as the one, who has an experience of teaching English language for many years, has felt in action that vocabulary and speaking are closely and extensively related to each other. This book would be of benefit to English Language learners to promote their knowledge of vocabulary which leads to a better level of speaking skill and also would help both teachers and learners as Shokrollahi and Baradaran (2014) have maintained that, "Teachers should carefully assist learners to make appropriate choices and to motivate them to expand their capabilities by considering them as active participants in the teaching and learning process"(p.25).