The root of a language is vocabulary. Without adequate vocabulary, one cannot describe one's thoughts and feelings. Stahl (2005) defines vocabulary as knowledge of a word that involves not only a definition, but also how words fit into the world. This is also supported by Qing Ma (2009) saying that knowing the meaning of words and how to use it appropriately in different contexts is defined as vocabulary. It cannot be denied that vocabulary plays a major role in determining a person's language skills because vocabulary is the core of language skills. Generally, learners find it difficult to express their thoughts and feelings due to inadequate vocabulary. This problem is quite common among second language learners. Anderson and Freebody (1981) in Baumann (2005) wrote that reading comprehension and vocabulary shared a strong connection that was recognized 80 years ago. Ediger (1999) in Donohue (2000) found in his research that insufficient knowledge of functional vocabulary is one of the reasons why students do not read well. Donohue (2000) stated that it is necessary for students to have some prior knowledge on the topic to ensure understanding. The close connection between students' prior knowledge and the subject matter impacts how students understand a text. Kasper (2000), in Bourn (2012), states that this theory was established based on communication between learners' background knowledge and texts, resulting in understanding. This can be confirmed by the study conducted by Liu Na (1985). Liu Na found that students should cover 95% of the text. Students' familiarity with the subject also influences their ca...... middle of paper ...... difficulty Benjamin (2009).The aim of this research is to enrich students' vocabulary by using cues contextual. By mastering the skill of context clues, students would not need to rely on a dictionary or other sources to find the meaning of unknown words. Students lose interest in the text if they need to refer to the dictionary every time they encounter difficult words. Educators can also benefit from this research where they will be exposed to various types of context clues in which they can use them to expand students' vocabulary.1.3 Objective of the ResearchThis study aims to determine the degree of use of context clues to improve students’ vocabulary. In addition to this, this study also aimed to find out what type of contextual clues students are most familiar with and finally the reaction of students when they encounter unfamiliar words in a text..