You      drive on the right of the road in China. It’s the traffic rule.

— I phoned you yesterday morning. A girl answered, but I didn’t recognize the voice.— Oh, it ____ my younger sister. She was in my room at that moment.

---Will you stay at home until your sister comes back? ---Sorry, I _______. I have a meeting and have to go in ten minutes.

When we were young, every evening my brother and I ___ stay at home waiting for my mother?

I have two cats. One is black, and ______ is white.