notion

The professor challenged the traditional notion that economic growth always leads to increased happiness.

(Chinese) 教授挑战了那种认为经济增长总是会导致幸福感增加的传统观念。

I had no notion of how difficult the mountain hike would be until we reached the steep pass.

(Chinese) 直到我们到达陡峭的山隘，我才知道这次登山远足会有多困难。