问题补充:
What will the world use for power when it oil?
A. run out of
B. is running out of
C. has run out
D. has run out of
答案:
A. run out of
B. is running out of
C. has run out
(答案→)D. has run out of
解析:考查词组和时态:run out和run out of,run out是不及物动词短语,没有被动式,run out of是及物动词短语,主句是一般将来时,从句用一般现在时或是现在完成时,句意:当世界用完了石油将用什么做为能源?选D。