Пожалуйста помогите с английским

Укажите, в каких из этих предложениях есть ошибки в употреблении времен. (Напротив каждого из предложений выберите +, если верно, - — если неверно).

1)They were chatting excitedly as they were driving down to the south coast.

2)As they looked up, they had seen a strange object in the sky.

3)After Helen had been doing the laundry, she decided to have a rest.

4)Salvador Dali and René Magritte had been two famous Surrealist painters.

5)The wind was blowing fiercely as we knocked the door.