Question

Polar bears live mostly on __________ sea ice, which they use as __________ platform for hunting seals.

A．a; a

B．a; the

C．不填; a

D．the; 不填

Answer 1

C

第一空后的sea ice为表泛指的物质名词，故其前不用冠词; 第二空后的为表泛指的单数可数名词，故其前用不定冠词。