I can’t speak french, but if I saw something written in that language i’d probably be able to say “Oh, that’s in french” despite not actually knowing what it says. You can recognise languages by what they look like even if you don’t speak them.
I guess this is probably a question for people who didn’t speak english at one point, then; how do you identify english? What stands out about it in comparison to other languages?
Back when I didn’t speak English, I wouldn’t have been able to distinguish it from Dutch or German. I would have known it was “not a romance language, European, not Scandinavian (no crossed out letters)”. If I’d learned German before learning English, I still would probably have problems distinguishing it from Dutch unless I had some sort of context information.
I’m a native English speaker. However, I had a weird experience one day coming home.
I’d been at an Esperanto-speaking meeting. I was reading a French comic book. I got on my bus and as I was sitting down, noticed a lady reading a newspaper with headlines written in an unfamiliar language. It appeared tio be a mutant relation of Dutch, with not as many vowels and lots of consonants like Ts and Hs.
Suddenly, something clicked in my brain, and I realised I was looking at English headlines in the Toronto Sun. Just for that moment though, I was looking at English from outside. It was quite an eye-opener.
High frequency of “the” is supposed to be one of the best tipoffs.
Yeah, but it requires you to have some knowledge of the language. Lots of -ing terminations too, but again it requires you to have some specific knowledge.
Of course, since English is so all-pervading, everybody knows more English than they think (it’s even the theme of a current ad for a Spanish EFL school).
In the late 1990s, I stumbled on a dummy text generator that, along with lorem ipsum, would generate paragraphs that looked like various European languages. The English text it generated didn’t look a thing like English, but to the eyes of a non-English speaker, it’s probably close. To my eyes, the fake French and German looked almost indistinguishable from the real thing. I know a bit of Spanish, and the fake Spanish dummy text it generated based seemed obviously fake, but still a bit Spanish-y. I think the more familiar you are with the language, the less familiar the fake versions of it will seem.
Here’s another fake English generator I just found. The quality doesn’t seem that good; it just seems to lob together real words, including obscure and archaic terms, from a massive English dictionary and other source texts.
[snark]One distinguishing characteristic is that the names of languages are capitalized. 
[/snark]
I believe you have the contents of my spam folder.
Sorry. I assumed that, in order to know the identifying characteristics of a language, one would have to have some knowledge of the language. …?
I don’t know about Dutch, but German capitalizes all nouns, so if you saw lots of sentences in which nothing was capitalized except the first word of each sentence, you could probably rule out German.
English does not decorate any of its letters with those goofy little marks (accent marks, um lauts, etc.), except perhaps occasionally on words that were borrowed from other languages or names of heavy metal bands.
That’s actually a pretty strong tip-off for English. Given enough text, it really stand out from other languages that use the Roman alphabet.
Here’s a handy one for differentiating the largest three Scandinavian languages (and I’ll bet I’m blowing it, but what the heck?):
Swedish has å but not ø.
Norwegian has ø but not å.
Danish has both
The joke is that if you compare notices on European trains for example the French version will be twice as long as the others, the German will just be one long word, English the most concise.
Doesn’t help if you have nothing to compare to though.
I’d hazard a guess that English has more shorter words than other roman alphabet languages, fewer consonant clusters and a lack of words ending in vowels (except “e”).
Yeah, you blew it. There’s no difference in Danish and Norwegian, alphabet wise.
This very question – both what it looks like in print, and what it sounds like to non-English speaking ears (there’s an oxymoronic mixed metaphor for ya’, Slappy!) has occurred to me many times, but I always thought it was an over-active thyroid that caused thoughts like that. I’ve also wondered, what does an American accent sound like in German or French?
For obvious reasons it’s hard to verify for me, but I heard that an average American who wants to know how his accent sounds to German ears should imagine a severe case of a stereotypical old-fashioned southern accent.
Every language has distinct letter-use statistics. A computer can use these to guess which language a text is written in. They are also used in cryptanalysis.
I had second thoughts 
I gotta have another look at my Berlitz guides … could have sworn there was an easy visual distinction to make between written Norwegian (probably Nynorsk?) and Danish. The alphabets are the same, but perhaps there are some conventions that are different?
For comparison’s sake … let’s consider how some other Roman-alphabet languages stand out visually:
French – common use of é and è, word endings like -é, -it, -ie, -ière, -ien (-ienne). Frequent use of digraphs ou and ai. Common short words include de, du, au, la, le, pas, ou, avec.
Spanish – common use of final -o and -e. Suffixes such as -ia, -ción, -idad. Use of the letter ñ and of -rr-. Initial ll-. Common short words include el, la, de, del, hay, no, con.
Italian – A strong majority of words end in vowels. Frequent use of double consonants, especially -cc-, -gg-, -tt-. Use of -gl- and -gn- internally within a word. Use of initial sg-, sb-.
Portuguese – the ubiquitous ending -ão is the usual tip-off. Also, use of internal -nh- and -lh-.
Finnish – Greater frequency of y and h than in English. Use of ä and ö. High frequency of double letters. Absence of b.
Hungarian – Frequency of the digraphs -ty-, -gy-, -ny-, cz-, sz-, zs-. Use of double-accented ő and ű, as well the five basic vowel symbols with single accent (á,é,í,ó,ú).
Polish – Use of the letters ł, ę, ą, ć, ś, ź. Frequent use of rz, cz and final -ch, -ego. J and w occur more than in English.
Dutch – Frequent use of -ij-, -oe-, -aa-. Double o and the lone letters v and k will appear more often than in English.
…
English surely has similar markers – th has got to be a major one.
Joyce could have saved himself a lot of time if he’d had access to this program.
As a Spanish native speaker and raised in the Texas-Mexico border, what stands out fast while reading it is “The” as in “The car is parked in the garage.”