You have no ___ at all of how difficult my life was in those days.

A. 不过我认为用idea 更像英文！
不同意见，请指教！

A

A

A 意思相信你应该懂的吧！

A
concept

n.
观念, 概念

同义词 idea notion opinion thought

yes,i think" idea" is better than "concept",though concept is the correct one here.that is why i hate having test.