"We asked all the children if a certain illogical sentence was grammatically correct: “Apples grow on noses.” The monolingual children couldn’t answer. They’d say, “That’s silly” and they’d stall. But the bilingual children would say, in their own words, “It’s silly, but it’s grammatically correct.” The bilinguals, we found, manifested a cognitive system with the ability to attend to important information and ignore the less important."

I suspect that they didn't use the word grammar, but somehow got around it, asking if the sentence was correctly formed or something.

Of course, it's also possible that having parents teach you 2 languages practically forces them to teach about grammar early on, so they had an unfair advantage.

But I can very well image, that you gain a better understanding of grammar, when you speak two languages, almost by definition. This trick is also used in Natural Language Processing to improve part-of-speech tagging.

Of course, part of that could also be a result of my tendency to think about grammatical correctness in terms of type systems.

The issue is 'a' vs 'the' vs nothing:

    he went to the school
    he went to a school
    he went to school

'Chocolate' is another example of this, where the issue extends to the use of words like 'some', 'how many', and 'how much' (countable vs. uncountable quantities). Even if a person understands these concepts, it's still difficult to propagate it through a sentence so that everything type-checks (subject-verb agreement, etc), especially if you're coming from a language that doesn't have this kind of redundancy. It gets even harder with hypotheticals, where sometimes one might switch between both singular/plural and non-specific/specific mid sentence, all while English lacks gender-neutral singular third-person pronouns.

On top of this there are cases where the use of one over the other really just comes down to philosophy (whether native speakers of a language consider something distinct, concrete, or countable, or not). Similar issues come up with prepositions - which preposition goes with which verb differs even when describing the same concept in two very similar languages. (Best example I can think of at the moment is that in Japanese, people say "I bought it to her" instead of "I bought it for her"; I know English<->Spanish has similar issues, but my Spanish is rusty)

English is not my native language, but I don't think I have problems applying the work the. So I find that hard to imagine. However, my native languages are Dutch and German, which are probably the closest two languages to English in terms grammar. So, that could be a possible explanation.

I read that children learn to pronounce the th sound quite late. And this is generally a give-away for of non-native speakers. Could it be that you are confusing this with that ?

However, I was referring to the actual usage of the definite article, not its spelling. I think the problems here are of two different kinds:

Those who come from languages where there is no definite article (e.g. Chinese, Turkish) struggle to understand the correct usage. This is one of the most common glitches I hear from my Mandarin speaking colleagues (in addition to omitting plural forms).

Not all IE languages have articles, i.e. Hindi, Russian, Latin. Simplifying thing, one may say that English is a curious mixture (or bastard :-) of French and Anglo-Saxon, both of which has articles. It shed a lot of its grammatical rules over the centuries (e.g. noun declension, verb endings) but still carry vestiges, like the appendix, which is what confuses other IE speakers. These errors, tend to be the opposite of the Mandarin case, i.e. the over-regularization of the usage. My wife, who is near-native in French, does this frequently in her English usage.

This brings to mind a slightly different topic: The prediction of gender for (genderless) words adopted from English, i.e. if you are German and see the word iPad for the first time, which gender do you use? This study (http://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.132...) tackled this problem for Scandinavian languages and found that it is quite difficult, they get ~70 accuracy.

The working class accent for where I'm from (Dublin, Ireland), prounounces "th" as "d", so "the" can be said "de".

A german friend advised his mother (who's is an english teacher (in germany)) to teach her students this, since it's easier for germans to pronounce!

Indicative that: "Which apple do you want?" "That apple." "This apple?" "No, that apple."

Causative that: "Why did you go to school?" "So that I could study Japanese."

Antecedent that, where that takes the place of some concept which has come before: "Did you study Japanese?" "That is a given."

"Never going to see it outside of literary constructions" that: "That which cannot be seen is more real than that which cannot be felt."

Adjectival-clause-introducing that: "We are looking for two students that are studying language pedagogy."

etc, etc

English grammar, fun stuff.

Fascinating stuff!

'Which' wouldn't be used here because 'are studying language pedagogy' is restricting/filtering 'students', and so it's essential to the meaning of the sentence. 'Which' is used for clauses that add non-essential information.

    My shirt that is red is upstairs.
    My shirt, which is red, is upstairs.

Bilinguals don't translate from 1 language to another, they actually think in that language while using it, to the point that you can actually see attitude changes based on which language they are using.

I know I don't think in code, but rather translate it from English into whatever programming language I'm using.

Really? I think the only time I do this is when something is sufficiently tricky that I probably have to draw it to work out what it should be doing ("Ok, so I pass this in here, and then it could flow through to here or here..."). Otherwise, assuming I'm sufficiently fluent in the language I'm programming in it just "flows" out, as when I'm speaking in Spanish (a second language I speak well) - there's no intermediate translation from English in either case.

Coding is the same way... I think "I'll loop over that" and then proceed to write out how to do it in whatever programming language I'm working with. Sometimes I even write comments in English and then go back and fill in the code that does what the comments want.

You are not there yet. Here's why. In pre-fluency stages of language acquisition, the taxing part of language parsing is memory retrieval, iow, mapping meaning from language A to language B. If you are well-versed at this, it can happen sufficiently quickly. For example, "a machine with four wheels that brings people places" --> car. After enough practice, you "bypass" the "machine" and retrieve "car" without consciously looking up the word. Imagining that happening for every single word, and every single sentence construction. That's when you're "there".

As for coding, there is an easy example: iterative looping vs. map/reduce operations. These can express the logic but are conceptually different: one is to repeatedly track states across some number of times, the other is to apply a transformation function to a set of items. To reuse the car analogy, a looped factory would be like taking parts and assemble 100 cars, and a map factory would be like taking parts and assembling all the wheels, then all the engines, then all the doors and so on.

Absolutely agree! I keep telling my friends (who are forever translating between English and their native tongues) and my father (who is a professional translator) that it is not always possible to translate accurately because languages are deeply rooted in the culture/habits of the people who use them.

I'm bilingual and I find that sentences spring to my mind in the language that I've been using in the last week. I speak my native tongue in my parents' home and English everywhere else. I stay for a week in my parents' home once every four months.

However, sentences do not always spring to my mind. I think more in images and senses than in language.

I don't. I usually don't think in language at all. Both speaking my native language and programming require translation from the abstract symbols and feelings that my actual thinking consists of.

Now aday with object oriented languages, I find myself thinking in Smalltalk first then translating the concepts to the given language.

Almost certainly. I don't have a reference but I remember reading an article about a couple who were both neurologists. They were both in their 60s IIRC, and they each took on a new arbitrary hobby each year to exercise their brains. It could be anything, as long as it required a non-trivial amount of concentration and mental effort. I'll see if I can dig the article up, it was really interesting.

When writing C, I don't feel like I'm "translating English into C" as somebody else said, rather I "think" in C: in pointers, in functions, in arrays, in structs... Likewise right now I'm not translating my native language into English, I just think and write in English.

I also experiment the same kind of frustration when I have to write something in a language I don't know well (be it Python or Russian). I don't know the vocabulary, I have to look up everything on the web all the time to find out what's the right way to express something. Some parts of the grammar seem backwards and you try to say things in one language the way you would say them in an other, and it ends up in a complete mess (and often, you blame the language, see that "C is better than C++" thread that was on the frontpage earlier).

That being said, it's pretty obvious that learning a programming language (even something as big as C++) is orders of magnitude simpler than learning a foreign language, so I would not say that knowing Python and Prolog is nearly comparable (or as big an achievement) to knowing Japanese and Arabic. On the other hand, we use programing languages to solve complex problems that always require some mental effort when speaking a language becomes completely natural once you're sufficiently fluent, so I suppose both may be beneficial to the brain in the long term.

The authors did go to some effort to rule out other causes of correlation, though: "The effect does not appear to be attributable to such possible confounding factors as education, occupational status, or immigration. Bilingualism thus appears to contribute to cognitive reserve, which acts to compensate for the effects of accumulated neuropathology."

The second language is crucial because it provides basis for comparison. If all you've ever used is Internet Explorer, that's the entirety of your internet experience. But if you've tried just another browser, you learn to appreciate the difference.