Assessment is an important activity in any educational process to evaluate the learner's knowledge about the concepts learnt.Evaluation through objective testing is common in all evaluation system, where Multiple Choice Questions, Fill in the Blanks, Matching etc. are used for evaluation. The method of objective testing is not sufficient to completely verify all the concepts learnt by the learner. Thus computer assisted assessment of short text answers is developed. Here we present a technique which also considers grammatical errors during automated evaluation of one-line sentences. In this research we defined a set of evaluation criteria that covers all the relevant aspects of an essay assessment system and discuss how this technique find syntactical errors during evaluation of student response.