As there is less and less coal and oil, scientists are exploring new ways of making use of ____ energy, such as sunlight, wind and water for power and fuel.
#18985
A
original
B
alternative
C
convenient
D
staple
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Please don’t bother me again. I’ll inform you of the details at a/an time if you must know.
#19390
A
appropriate
B
convenient
C
acceptable
D
accessible
Although I can walk about, there is still a _____ pain in my leg.
#18993
A
weak
B
soft
C
gentle
D
slight