I have aleady waited here for hour and half.A. an….aB. a….aC. a…..anD. an….an

问题补充：

I have aleady waited here for hour and half.

A. an….a

B. a….a

C. a…..an

D. an….an

答案：

(答案→)A. an….a

B. a….a

C. a…..an

D. an….an

解析：不定冠词an用在以念元音开头的词之前，a用在以念辅音开头的词之前。