Norsafarova Nilufar. “Grammatical Differences Between Adverbs and Modal Words”. American Journal of Language, Literacy and Learning in STEM Education (2993-2769) 1, no. 8 (October 23, 2023): 390–393. Accessed December 22, 2024. http://grnjournal.us/index.php/STEM/article/view/1064.