两个都不是
I had difficulties climbing moutains
是我有困难攀登山峰
I had difficulty climbing moutains
是我难以攀登山峰
正确答案是I had difficulty climbing the mountain
两个都不是
I had difficulties climbing moutains
是我有困难攀登山峰
I had difficulty climbing moutains
是我难以攀登山峰
正确答案是I had difficulty climbing the mountain