1) It's a beautiful day. 2) i have to practice more. 3) most students of my group were born in st. petersburg 4) 4) he was able to swim the english channel Сделать вопросительными.

Чтобы сделать данные предложения вопросительными, просто ставим глагол to be или любой другой вспомогательный глагол в нужной форме спереди (is, do, were, was и т. д.), дальше ставим местоимение или существительное (it, I, students), а потом и нужный глагол или слово (beautiful, born и пр.)

1) Is it a beautiful day? 2) Do I have to practice more? 3) Were most students of my group born in St. Petersburg? 4) Was he able to swim the english channel?