shows that learners with better vocabulary knowledge score higher on achievement test.
4 Enhances thinking and communication Words are used by the language user to analyze, infer, evaluate and
reason. Large vocabulary knowledge allows language user to communicate in precise, powerful, persuasive and interesting ways.
c. The Nature of Vocabulary Acquisition
Different with listening, speaking, reading, and writing, vocabulary has its own characteristic of how it is understood by the learners. Hiebert Kamil
2005: 2 states that “vocabulary is not a developmental skill or one that can ever be fully mastered. The expansion and elaboration of vocabularies is something
that extends across a lifetime”. It is almost impossible to understand all of the vocabularies of a language because language is about words and there are so many
words that registered in certain language and even language itself is always develop and also change. The knowledge of vocabulary will be developed along
with the learner’s occurrence with the language. So, it is expected that the more the learners deal with the language the more knowledge of vocabulary that they
can learn. Schmitt 2002 proposes that an advanced language learner knows
approximately ten thousand words. There is a difficulty in understanding of how learners learn those huge amounts of words. However, vocabulary acquisition has
some essential features. First, vocabulary acquisition needs a gradual learning of different knowledge that belongs to single word its spelling, its meaning, its use,
etc. Concerning with its numerous aspect of understanding, the learning process of vocabulary acquisition cannot be done at once.
He adds that there are some features dealing with vocabulary acquisition. One of those features is concerning with vocabulary acquisition’s incremental
nature. It refers to the gradual learning of different knowledge types that belong to a single word. The word cannot be fully learned in one time. Based on his
research, he states that learners first learned a words’ spelling, then the meaning of the words. There is also a continuum which the learners learned a word’s basic
meaning first and then learned other meanings of the word. It means that complete knowing of a word takes time.
The next feature is that vocabulary acquisition also deals with the distinctive between receptive and productive vocabulary. Receptive vocabulary is
those which used to recognize and understand a word in written or spoken, however productive vocabulary is those which used to enable learners to express
their meaning. Learners have to be able to recognize the different and the usage of those kinds of vocabulary.
The last feature is about retaining fragility. The learners may forget some knowledge about words in the process of vocabulary acquisition. Especially in the
L2 learning, the learners more likely forget lexical knowledge than grammatical knowledge. So, vocabulary knowledge should be recycled systematically so the
learners can retain the knowledge. Furthermore, the fragility of vocabulary knowledge exists because “vocabulary is made up individual units rather than a
series of rules”. Therefore, whether vocabulary items are learned partly or
completely, they should be recycled systematically to help strengthen the retaining process.
Vocabulary acquisition is processed by immersing the learners in certain kind of exposure over a period of time. Those exposures will affect the learners
when they are dealing with English. Some occurrence such as when the learners of L2 feel like they have seen a particular word in a text or hear the words in
certain conversation showed that they are in the process of vocabulary acquisition.
d. Vocabulary Size and Vocabulary to be Learnt
Thornbury 2002: 21 states that to be able to join conversation in daily communication, learners should know at least 2000 words. These are words that
used in dictionary for language learners which native speaker usually used in daily communication. He also states that knowing 2000 words make the readers
understand nearly nine out of ten words in most of written text. In relation to the reading comprehension, the first 2000 high frequency
words serve 80 of words in English text. Understanding all of those words makes the learners considerably to be described as having a good degree of
comprehension of a text. In learning English for General purposes, the learners need to understand the most frequent 2000 words of English to have a good
reading comprehension of a text. However, in reading academic texts, the learners need to understand 1000 more words from the most frequent words of academic
texts Nation in Hiebert and Kamil, 2005. The words that they should know include word families in which a base word and all of its derivation and inflection
is count as one Cameron, 2001. Regarding those vast amounts of vocabulary,
