Instructor presence in online teaching: challenges and opportunities Tatiana Leonidovna Kopus, Elena Sergeevna Mikhalat, Ekaterina Yurievna Belozerova and Olga Vladimirovna Meshcheryakova SHS Web Conf., 127 (2021) 03002 Published online: 02 December 2021 DOI: 10.1051/shsconf/202112703002