“…Findings revealed that the researchers in this study employed boosters to express certainty or to emphasize a point (Dobakhti, 2013;Holmes, 1990;Hyland, 2000;Jalilifar, 2011;Macintyre, 2013). In other words, boosters were used as a certainty marker (Koutsantoni, 2004) or simply as an emphatic (Abdollahzadeh, 2011). They used boosters to put emphasis, add commitment, and express certainty to the claims they made (Holmes, 1990;Hyland, 2000) and to express commitment (Macintyre, 2013).…”