Mary poppins is doing some shopping with the children. she has a long shopping list. they have already been to the grocers and have bought sugar, bacon, salt and rice. . надо определить время, рассказать о нём а потом перевести в время, .

Время present continius используется при действии происходящем в данный момент образуется при глагола to be ( 1 л ед ч - am, 3 л ед ч - is, мн ч - are) и глагола с окончанием ing. 
Mary Poppins was doing some shopping with the children. She had a long shopping list. They had already been to the grocers and had bought sugar, bacon, salt and rice.