I tried to work on, but I was so tired that I could no longer ___.
Everywhere man has cut down __________ forests in order to grow crops, or to use __________ wood as fuel or as building material.
)According to __________ World Health Organization, health care plans are needed in all big cities to prevent __________ spread of AIDS.
For him __________ stage is just __________ means of making a living.
Of all __________ reasons for my decision to become a university professor, my father’s advice was __________ most important one.
— I knocked over my coffee cup. It went right over __________. — You shouldn’t put drinks near __________ computer.