Our knowledge of computers _____ growing all the time. [ ]
A. be
B. is
C. are
D. were
答案:B
早期市场
下列词语中,一定包含有化学变化的是( )
A.石蜡熔化
B.轮胎受热爆炸
C.蜡烛燃烧
D.滴水成冰