The boy has not had a stomachache since he _____ eating fast food.
A.stops B.stopped C.will stop D.is stopping
The lab can be dangerous, so we________ always wait for the teacher to arrive before we start work.
A.may B.can’t C.must D.needn’t
Be ________ careful with the door. Shut it when you’re in and lock it when you go out.
A.suddenly B.especially C.finally D.probably
— Did you understand the opera, Betty?
— No, it was difficult to understand the words. But the actors and actresses were________.
A.excellent B.comfortable C.dangerous D.delicious
The World Health Organization________ and controls serious diseases.
A.enters B.invites C.prevents D.regrets
Chinese people are brave. We are not afraid of winds and rains, or any kinds of________.
A.difficulties B.instruments C.memories D.exhibitions
