The slope on either side was extremely steep and forbidding, and yet I thought that I could work my way down on either side.

两边的山坡极其陡峭，极其险峻，然而我觉得从哪边都可以爬下去。

youdao

Construction technique of concrete lining of long inclined shaft with steep obliquity Angle and large diameter is complex and extremely difficult.

陡倾角大直径长斜井混凝土衬砌施工技术复杂，施工难度大。

youdao

She said it would be unrealistic to expect agencies facing an "extremely steep learning curve", with little experience of construction on this scale, to get things 100% right first time.

BBC: UK aid 'left legacy' after 2004 tsunami in Asia

As long as China, alone, continues this steep growth trajectory, albeit aided by extremely loose monetary policies (i.e. the printing of money), the worldwide demand for commodities will remain strong.

FORBES: After The Gold Rush -- Commodities Prices: Why So High?