It snowed for days on end. We thought it would never come to end!A. an;anB. an;/C. /;anD.

问题补充：

It snowed for days on end. We thought it would never come to end!

A. an;an

B. an;/

C. /;an

D. /;/

答案：

A. an;an

B. an;/

(答案→)C. /;an

D. /;/

解析：考察冠词。考察固定词组。On end连续地；come to an end结束；结合句意可知C正确。句意：已经连续下了好几天的雪了。我认为它不会结束了，会一直下下去的。