The reason _______ he was late was _______ he missed the bus.
A．why, that B．why, because C．that, why D．because, why
The tiger, once a ____ animal to humans, is now ____ of disappearing on the earth.
A．dangerous, danger B．dangerous, in danger
C．in danger, in danger D．danger, in danger
We shouldn’t spend our money testing so many people, most of ____ are healthy.
A．that B．which C．what D．whom
I won’t see the film tonight. I am busy. ______, it is raining cats and dogs.
A．Beside B．However C．Besides D．As well as
Computers in offices and homes since 1970s．
A．have been used B．had been used C．was D．has been used
More attention must be paid the endangered animals..
A．protect B．to protect C．to protecting D．protecting
