Vocabulary and its appropriate use play a crucial role in second language learning and teaching.However, vocabulary acquisition in EFL education failed to receive the attention it deserved.Collocations have a significant role in EFL teaching and learning as they develop the learners' proficiency with lexis. Lexical approach gives special attention to teaching and learning collocation. Although most of the studies have proved the significance of collocations, researchers have pointed out that collocations are a serious problem for second language learners and one of the difficult parts of vocabulary learning for them including advanced learners and professional translators and they always hesitate over which words go hand in hand with which correctly. This book therefore tries to investigate the impact and significance of knowledge of collocation all four language skills.The results of the study will direct teachers' attention to focus on collocations, and it will present useful ways for teachers to implicate a better understanding of the nature of English collocations and their effect on four language skills.