I don’t think dropping litter is allowed in Yellow River Park, ________?
— _________ will the concert start? — In about five minutes.
Beijing, the capital of China, is one of _________ cities in the world.
You ________ cross the road when the traffic lights are red.
I invited four teachers and ________ can come. That’s great.
They travelled all night to the village and got there ________ Sunday morning.