People on the grassland ofisnow Kazakstan were the first to achieve both riding and milking horses．

Why didn’t you come to Mike’s birthday party yesterday?　　— Well, I ____, but I forgot it.

We work together to achieve our common purpose: __________ world that is safer, cleaner and healthier than __________ one we are living in.

_________ the fans are waiting for the popular singer outside the concert hall.

I never go to school late, .