If we are interested in something, our brain is ________ and it is also easier for us to pay attention to it for a long time.
A.active B.more active C.the most active
Since 1990, Project Hope ________ millions of students from poor families realize their dreams.
A.will help B.has helped C.helps
The BBC's documentary Du Fu：China's Greatest Poet explains ________ Du's works have been popular for centuries.
A.when B.whether C.why
With the help of Air Classroom, students ________ keep learning even with schools closed.
A.can B.must C.should
Drugs are harmful to people's physical and mental health. We teenagers must ________ them.
A.take care of B.keep away from C.get used to
—Pingtang Bridge has the highest concrete bridge tower in the world.
— ________ amazing it is!
A.How B.What C.What an
