A warm thought suddenly came to me _______ I might substitute the hero to buy some flowers for his mother’s 60th birthday.
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.
Dogs are kept to ______ the houses from thieves at night.
Because of the accident, the road was ________ to traffic.