past continuous and past simple

My brother and sister were arguing about something when I (walk) ___ into the room.

I called Roger at nine last night, but he wasn't at home. He (study) ___ at the library.

While Ted (shovel) ___ snow from his driveway, his wife bought him a cup of hot chocolate.

(Hear, you) ___ what she just said? No, I wasn't listening.

Tom went to his friends' house, but the boys (be, not) ___ there. They were playing soccer.

I almost had an accident. I was driving down the road when suddenly I (see) ___ another car!

I am sitting in class right now. I (sit) _____ in class at this exact same time yesterday.

I got a package in the mail. When I (open) ___ it, I found a surprise.

Stanley (climb) ___ the stairs when he tripped and fell. Luckily, he didn't hurt himself.

Why weren't you at the meeting? I (wait) ___ for a skype call from a client.