I were walking in the park when she rang — Я гулял в парке, когда она позвонила;
Tim was cleaning the room when the guests arrive — Тим убирался в комнате, когда пришли гости;
The girl was looking for the book when i came in — Эта девушка искала книгу, когда я зашёл;
We were having a picnic an hour ago — Час назад у нас был пикник;
His parents were playing chess when i came in — Его родители играли в шахматы, когда я зашёл;
The astronauts were looking at the sky the whole evening — Астронавты смотрели на небо весь вечер