Abstract:
This study attempts to investigate the relationship between vocabulary Knowledge of EFL students and
their reading comprehension of authentic texts in Ethiopian context. Above all, the thesis tries to examine
the percentage of known words students need to guarantee reading comprehension of authentic texts. The
data for the research was collected from sixty-one Woldiya Preparatory School grade 12 students. Three
reading comprehension tests, circling the unknown words in texts and a lexical coverage test for each text
was given to the subjects. The data analysis from the tests shows correlation coefficients of
r=0.48,moderate (r2=23% of the variability in this reading comprehension test results could be explained
by the percentage of known words) for text one; 0.83, strong (r2=69% of the variability in reading
comprehension test results could be explained by the percentage of known words) for text two; and 0. 73,
Substantial (r2=53.3% of the variability in reading comprehension test results could be explained by the
percentage of known words) for text three. Here in this specific project 48.4% of the variability in the
ability of comprehending authentic reading texts could be explained by the percentage of known words.
All the texts showed that there is a positive relationship between known words and reading
comprehension scores. The results indicate that the subjects needed to know 94. 2% of known words to
comprehend text one, 89.9% of known words to comprehend text two, 92.4% of known words to
comprehend text three. In general, in all texts the subjects needed an average of 93% of known words to
comprehend authentic online article reading texts adequately. In other words, in the three authentic
reading comprehension texts, the subjects needed an average of 93% of vocabulary knowledge to score a
minimum of 50%. Based on the .findings, this study tells that there is a lexical threshold for EFL students
below which adequate comprehension of authentic texts might be impossible. Further studies by adding
more independent variables should be conducted with EFL students at different grade levels, using
different types of authentic texts. It is because 77% for text 1, 31% for text 2, and 46. 7% for text 3 of
reading comprehension test scores was not based Of! tbffpercentage of known words for this study.
