This study aimed at investigating the alerters produced by 200 Sudanese university students in their written response to two Arabic and English Discourse Completion Tasks. The study attempted to classify the different types of alerters collected using the two tasks based on their nature. Then, it compared and contrasted the precursors used by the subjects in the two languages. The study also examined the different functions of alerters produced by the participants. Moreover, it explored the impact of social distance, power relation, and degree of request imposition on the participants' choice of precursors. The study showed that Arabic utilizes precursors more often and with wider variety than English. Arabic displayed a total of sixteen types of alerters while English used eleven only. It was also found that the precursors were used to perform a variety of religious, social, and pragmatic functions. Moreover, it showed that different contextual factors influenced the subjects' choice of alerters.