Edison who invented light had _________ knowledge of science.
| A．a; \ | B．a; a | C．the; \ | D．the; a |
Our teacher told us____an electric bike.It’s too dangerous.
A.to ride B.not to ride C.not ride
—Why didn’t you ask me to help you with your work?
—You are so busy. I won’t ___________ much of your time.
A. take up B. take off C. take to
The number of the students in our school____about 1000 and a number of them____boys.
A. are ;is B.is;is C.is;are
The book is worth____.
A. to read B.reading C.read
The river has become much ______ than before because of the waste water from the factories.
A. dirty B. dirtier C. Dirtiest