My mother is a writer.She________more than ten books since 1988.
The flood _____ about _____ people since it happened.
What _____ it is to go camping in _____ weather!
---- How does your father usually go to work?---- He _____drive a car, but now he _____ there to lose weight.
The math problem is _____ difficult that only _____ students can work it out.
________ fathers are both doctors.