He was very ill, but now he is out of danger.
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.
— You don’t look well, Don! You’d better see your doctor. — I ________, but he said there was nothing wrong.