Вставь past simple, past perfect, past progressive. last week we (to buy) a new car. while we (to buy) it, we (to see) our old friend. he (to be) glad to see us. we (to know) him before we (to see) him. while we (to talk), our children (to run), ( to jump) and (to break) on the ground. we (to be) upset.

Last week we bought a new car. While we were buying it, we  saw our old friend. He was glad to see us. We had known him before we saw him. While we were talking, our children were running, jumping and breaking on the ground. We were upset.