составить словосочетания

- is the first cake tasty?

- yes, it is.

- was the fourth lesson difficult?

- yes, it was. 

my  friend and i went to the superquiz. the tree monsters went to the  superquiz too. we answered some  questions ! we  were very happy. hooray!

1. i was sitting in front of the fire, when they called out to me.

2. i was getting the tea ready,  when my mother came home from work.

3. she was dusting the carpet, when her cat knocked a vase off the table.

4. we were finishing our tea, when there was a knock at the door.

5. they were going down the garden path, when she stopped and waved. 

1-с, т.к. после who ставится is, но т.к. есть last sunday как показатель прошедшего времени ставим was.  2-а, т.к they-множественное число, из предложенных вариантов подходит только а))