Is that boy Alan?—No, it ______ be him. He left for Beijing yesterday.

It was too cold and windy , so we could see ____ people walking in the street .

Can I walk across the road now, mum? — No, you_______. You have to wait until the light turns green.

Sandy,I called you at 9:00 last night,but nobody answered the phone.-I’m sorry. We ______ a birthday party _______ Jerry.

Lily and her sister look the same. I can’t tell one from_______.