1 задание

g. travelling

h. seeing

j. paying

2 задание

a. You were playing cards.

b. Alice was walking around the lake

d. We were reading a book about Australia

e. Beth was washing the car

3 задание

a. Sarah and Luke were not working together

b. Mr. Miller wasn't teaching Geography

d. Albert, Mandy and I were not playing tennis yesterday.

4 задание

a. Was Rachel feeding the cat?

b. Were the children painting a picture?

c. Was Clark repairing his computer?

d. Was I doing my homework?

e. Were Lucas and Hazel making dinner?

f. Were the children swimming in the swimming pool?

Ваши ошибки(если они конечно Ваши :D) связаны с невнимательным прочтением условия, ведь во всех заданиях нужно было использовать время Past Continuous, но в некоторых предложениях совсем другие времена. Будьте внимательны :)