You've finished running 8,000 meters. You ______ be very thirsty.
The World Expo (世博会) ____________ in Shanghai now.
Beijing, the capital of China, is one of __________ cities in the world.
How time flies! Three years ____________ really a short time.
I felt it hard to keep up with my classmates. But whenever I want to ____________, my teacher always encourages me to work harder.
— How long have you ________? — For three days.