3. Kate --- the antique vase while she --- the bookshelves. a. broke – cleaned; b. was breaking – was cleaning; c. broke – was cleaning; d. was breaking – cleaned

Перевод задания: Выберите правильные варианты.

c. broke – was cleaning. Kate broke the antique vase while she was cleaning the bookshelves. (Кейт разбила старинную вазу, пока убирала книжные полки.)

Разбитая ваза — отдельное завершённое событие (Past Simple), уборка в этот момент продолжалась (Past Continuous).