Number of Vocabulary Items Learners Must Know
Many researchers have tried to estimate the number of lexical items that native speakers of any language know to assess that how many words other than non-native speakers must know to learn the language. For a native speaker, this estimate varies between 12,000 to 20,000 words depending on the level of education (Goulden, Nation and Read, 1990). Exposure of a few words can lead to greater comprehension for non-native speakers. For instance, the students who have the knowledge of common20, 000 words can comprehend around 80% of them in a normal text and if the vocabulary is 50,000, words then learner’s understanding is increased to 88.7% (Francis and Kucrera, 1982). For spoken language 1,800 words make up over 80% of the spoken corpus.( Mc Carthy and Carter, 2007).