Of all the studetts, he prepares his lessons ___.
Don’t keep your mouth ___ if you want to improve your spoken English.
My classmate, Li Ming, was highly praised for ___ a good deed.
Sunglasses can ___ us from strong sunlight. A. hold B. prevent C. protect D, make
There are many pine trees on ___ of the street.
His father feels ___ his duty to help others.