It could be exhilarating, intimidating, sometimes even discouraging, but always challenging.

哈佛的生活使人兴奋，让人胆怯，有时甚至会感到泄气，但永远充满了挑战。

youdao

What I remember above all about Harvard was being in the midst of so much energy and intelligence. It could be exhilarating, intimidating, sometimes even discouraging, but always challenging.

我所记忆的哈佛一切是我活力和智力的中坚，令人或振奋，或可怕，或沮丧，但具挑战性，独具殊荣。

youdao

You will find this book sometimes challenging, sometimes startling, but always fascinating.

你可能会发现本书具有挑战性，有时又会使你大吃一惊，但总是你令你意想不到。

youdao

The fresh outside perspective of a brand new chief contrasted with the tried and true ways of a guy who had been there for many years following a familiar but always challenging formula of trying to make our ads stand out amongst the intense competition between the advertisers on Super Bowl Sunday.

FORBES: Super Bowl Past And Present: Anheuser-Busch Marketing Chief Talks With Past AB Marketing Chief

Asked whether it would ever be possible to prosecute a case under the 1925 Act, he said the law was "pretty straightforward" but any corruption case was always challenging as bargains made were never meant to come to light.

BBC: NEWS | UK | UK Politics | Key points: Cash-for-honours hearing

"Gone Baby Gone" isn't always a smooth ride, but it's a challenging, adult thriller guaranteed to foster fierce debate on the way home.

CNN: Review: 'Gone Baby Gone' is good, very good