she was writing a letter this time yesterday Jim had finished the work

问题描述:

she was writing a letter this time yesterday Jim had finished the work
he made a bookcase for his daughter
the nurse is looking after the baby
改为被动语态

1.A letter was being written by her this time yesterday.2.The work had been finished by Jim.3.A bookcase was made by him for his daughter.4.The baby is being looked after by the nurse.