Language learners

What's happening with language learning:

• One unknown word ruins a sentence: a single unknown word in a sentence can totally negate any meaning the sentence might otherwise give. If you have never heard a word before, for a native speaker you often have enough context and history to figure the part of speech, how it relates to the other words, who is doing what to whom. But to the non-native learner, it totally throws off everything. All the other words, which you previously know, may now have their meanings in question. And all the intellectual energy you're expending trying to figure out the unknown word is taken away from all the other words, making the known words, still shaky in this new language, even less sure. 

Statement by native speaker: "I went to the dumbledore to pick up some chicken and potato salad for the picnic"
Native speaker reaction: "dumbledore must be a grocery store."
Learner reaction: "Did you just call me a ... a bird?"

• A learner is lenient, a native is strict: To a native speaker, there are lots of collections of words that are similar sounding and have similar meaning but are not the same. For example, all the various word forms of a conjugation "has, have, had" or cognates ", To the native speaker, these individual words are all very distinct. Using one instead of another is a glaring error, a discordant note, banging your thumb with a hammer obvious. To the language learner, they're kinda the same. To someone foreign to both, Italian and Spanish are a lot alike, you can sorta make half sense of both about the same. But of course to them they are mutually unintelligible (but can pick out a few words here and there). To the learner everything close is good enough. To the native the slightest hint of a difference is shockingly noticeable, strange, and almost unrecognizable. This works for all areas: pronunciation, syntax, word choice. 

"I want the grocery store"
Native speaker reaction: "Want? That makes no sense. Did you want something at the grocery store? Did you want a grocery store? I don't get it."
Learner reaction: "Did you get chicken and potato salad?"

• Throw away step ladder: It seems universal in language teaching to start off with extremely simple sentences in the present indicative: "I read", "They eat". In English at least this is hardly ever used in practice. Surely there are short simple sentences that are actually used that can be taught.

What is (might be) taught: "I went to the cinema Fridays."
What normal people actually say: "I used to go to the movies every Friday."

• Translationese: word for word translation is easy and often a sentence can preserve meaning from one language to the next with a constituent to constituent dictionary translation. But often "that's just not how they say it in X". Frankly in English that's just not they say it (see the throw away step ladder).

What is taught: "That is correct"

Natural: "Of course", "Right", "Yes", "Sure", "I guess so"

• Style is not grammar: lots of rules are given (a consistent single rule to learn is much easier to remember than a more complex one) for which it is actually a style rule or a rule of register (formal vs informal). Also, most language teaching is academic and for a future business or academic use. In most languages (moreso but still a little in English) there is a big difference between the language called X in school and that called X at home. This can lead to a good language learner to be 'better' or excessively more formal than a native speaker. 

What is taught: "I must go to the pharmacy momentarily to obtain some sundries"

What people say: "I gotta go t'th'CVS 'n' pick up somethin' real quick"

• Humor and sarcasm: anything other than the most literal will not be caught by the language learner. The learner probably has no idea that the same sounds can mean very different things depending on context (forgetting cultural background altogether). On the other hand, when a learner does notice a homophone, they will find it the most hilarious thing in the world but it will barely register with the native speaker.

Lack of humor "Where do polar bears vote?"

Native speaker: "The North Poll!"
Learner: "I don't understand. Can polar bears vote?"

Basic Pun "Where do polar bears vote?"
Learner: "The North Poll! Ha ha! I get it! Because 'poll' sounds just like 'pole' but they're two different things, one is for ..."

Native speaker: "Groan. Also, polar bears can't vote"

The point is that someone learning a language is using all their mental energy to pick out the right sequence of words, to get the order right, pronunciation, to remember that one weird word, etc etc that it's the most unnatural thing in the word, and they sometimes miss the eventual meaning.