This study investigates the relationship between the age of onset of learning English and the ultimate attainment in that language. To this end, it tests the lexical and morphosyntactic competence of 62 intermediate school students who have different points of onset. They have to do a grammaticality judgment test and a vocabulary test. Using the methods of descriptive statistics, the result showed that late starters have outperformed early starters in all aspects of the language examined. The study also revealed that there is a relatively weak correlation between the age of headstart and the ultimate attainment in both levels of language tested. The correlations between the age of exposure and vocabulary attainment is (r = 0.2), whereas it is (r= 0.18) between the age of exposure and morphosyntactic knowledge. It is also found that there's a strong positive correlation between ESs and LSs grammar and vocabulary (r= 0.75). This suggests that vocabulary and grammar are interdependent fields in that the abstract morphosyntactic rules would remain null and void without the lexical component at work, and the intrinsic meaning of a vocabulary item can't be fully grasped without adequate knowledge of the morphosyntactic rules that assign meaning to each word in a sentence.