The falls have always been an insurmountable obstacle for salmon and sea trout.

这些瀑布始终是鲑鱼和海鳟鱼不可逾越的障碍。

《柯林斯英汉双解大词典》

Frank would enjoy playing in a different club and would be willing to leave Chelsea, but the financial issues seem an insurmountable obstacle at the time being.

弗兰克希望离开切尔西接受新的挑战，但是现在的情况是，资金问题是不能越过的障碍。

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Although this does present an obstacle for accessing the news from foreign countries, the obstacle is not insurmountable.

虽然这确实是来自大众的一个国外新闻障碍，但这障碍不是不可克服的。

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Despite the difficulties surrounding the election, neither analyst said Mr Havel's retirement was an insurmountable obstacle.

BBC: Czechs look to post-Havel life

But as we know today, this resistance did not ultimately prove an insurmountable obstacle to establishing mass public entitlements and normalizing the entitlement lifestyle.

WSJ: Are Entitlements Corrupting Us? Yes

And a low undergraduate GPA need not be an insurmountable obstacle.

FORBES: Tips For Getting Into A Top Business School