Ответ:

1) They did not live in London. 2) He did not watch TV at night. 3) Maria did not see her friend in the park.

They did not live in London.

He didn't watch TV in the evening.

Mary didn't see her friend in the park.

Пишется начальная форма глагола, потому что did забирает на себя прошедшее время.

Вроде бы так)