Tian'anmen Square is the largest square in the world, which covers a total area of 440,000 square meters, 880 meters north to south, and 500 meters east to west.
After his journey from Beijing during the National Day, Tom returned school, __________.
---The light was on all night long. ---Yes. It seemed that Mike ________. He was the last one to leave the office.
He became inspired when he thought about helping ordinary people _________to cholera.
At first, my new surroundings were difficult _________
There is a system ________the waste is disposed of using the principles of ecology.