Abstract:
This study examines omission errors, substitution errors and addition errors in the usage of prepositions by the learners of English as a Second Language (ESL) in writing tasks. The main purpose of the study Is 10 investigate: whether the school children in lower grades tend to omit prepositions more often than in highs? grades whereas in higher grades, they show more substitution and addition errors. A pool of 260 Sinhala speaking students from four grades (Grade 4, Grade 6, Grade 8 and Grade 10) participated in this study, picture story writing task where prepositions needed to be abundantly used was administered, and errors the use of prepositions were analysed. The main findings concluded; although more omission errors were found in the lower grades significantly, the increase in substitution errors towards higher grades is not w sharp. These findings can be used in the ESL classroom to facilitate teaching English prepositions.