— I hear it will rain tomorrow.— It _______ true. You see, there are so many black clouds in the sky now.
He was ______ medical student before he turned _______ engineer.
He’s so ill that his father has to send for _______ doctor.
Jumping out of _______ train running at a speed of 200 kilometers per hour is quite _____ dangerous practice.
________ your spirits. Try again and you’ll succeed.
As soon as Mr. Li came in, he asked Joan to ________ the books around the class.