---Alice, why didn’t you come yesterday?---I ____, but I had an unexpected visitor.
The tiger, once a ____ animal to humans, is now ____ of disappearing on the earth.
We shouldn’t spend our money testing so many people, most of ____ are healthy.
I won’t see the film tonight. I am busy. ______, it is raining cats and dogs.
Computersin offices and homes since 1970s.
More attention must be paid the endangered animals..