One reason why plane is such a popular means of transport is that it is very fast and safe.
A. the; /
B. a; the
C. a;/
D. the; the
网友回答
(答案→)A. the; /
B. a; the
C. a;/
D. the; the
解析：不定冠词a与可数名词plane连用, 表类指“飞机”这类事物; a means of transport为固定搭配. transport前不用冠词。