A few years ago, Top Gear host Jeremy Clarkson pointed out that the best way to expose a German spy would be to ask them to say the word "squirrel," because "no German, no matter how well they speak English, can say 'squirrel.'" So naturally, someone tested the premise and made a video of it. Here is that video (by Tamara Lenz) of 10 Germans trying to say "squirrel."
But don't feel bad, Germans! While we laugh, most of the world is cringing in sympathy with you. This word is nearly impossible to get right for anyone who isn't a native speaker of English! It starts with a pretty intense consonant cluster (which isn't a particular problem for Germans) and segues right into a syllabic r — the hardest English sound — and then immediately fades to the mushy "dark l." I mean, English speakers don't even really know how they say it. Is it one or two syllables? Is there really an r in there? Say it 5 times fast! Oops! Skwurrrl. Skwillrul. Skgrstasdfjkl. Get even the most eloquent native speaker thinking about it too much, and there's no way they won't start to fumble it.
And just to show this is all in good fun, here is a video of 10 Canadians trying to say the German word for squirrel, Eichhörnchen.