--- I heard they went skating in the mountains last winter.
--- It true because there was little snow there.
A. may not be
B. won’t be
C. couldn’t be
D. will be
网友回答
A. may not be
B. won’t be
(答案→)C. couldn’t be
D. will be
解析：考查情态动词：may not be可能不，won’t be 不会是，couldn’t be是否定推测，表示“一定不会”，根据because there was little snow there.可知选C，句意是：--我听说他们去年冬天去山里面滑冰了。不可能是真的，因为那里几乎没有血。