A. SO OFTEN B. AS OFTEN C. SO OFTEN AS D. AS OFTEN AS A. SO OFT...
98. A. so often
B. as often
C. so often as
D. as often as
Choose (A, B, C or D) to complete the passage:
There is now increasing concern about the world’s energy (99) ………
particularly about those involving fossil fuels. Unless than a hundred years we shall
probably (100)……… all the present sources of oil and gas. The world’s coal
reserves should last longer but once used, these can’t be (101) ………. It is
important, therefore, that we should develop such alternative sources of energy as
solar energy and nuclear energy as well as water and win (102) ……… class as
renewable energy. Until these energy supplies are widely used, it is important for the
develop countries to reduce energy (103) ……… as much as possible.