“…According to some studies in second language acquisition, vocabulary knowledge and grammatical knowledge have comparable effects on reading comprehension (Shiotsu & Weir, 2007;van Gelderen, Schoonen, Stoel, de Glopper & Hulstijn, 2007). However, others suggested vocabulary knowledge to be the better predictor (Brisbois, 1995;Haynes & Carr, 1990;Mecartty, 2000) and reported a significant correlation between vocabulary difficulty and text difficulty (François & Fairon, 2012;Heilman, Collins-Thompson, Callan & Eskenazi, 2007;Reynolds, 2016). While a number of computer-assisted language learning systems have addressed grammatical knowledge (e.g.…”