Does Stephen Krashen’s Input Hypothesis & Comprehensible Input Work for Learning Mandarin Chinese?

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Professor Stephen Krashen has arguably had more of an impact in the field of modern language education than any other academic linguist.

His Input Hypothesis – a group of five hypotheses developed in the 1970s and 80s, argues that comprehensible input is the key component required for successful second language acquisition.

Language education in schools and universities has traditionally been based on the belief that practicing speaking, vocabulary memorisation, repetition drills and grammar rules are the keys to learning a second language.

According to Krashen, however, studying information about languages in the form of grammar rules and practicing speaking through repetition drills are of marginal importance. Instead we acquire languages when we understand messages through reading and listening to our target language.

If we follow his principles, our task as language learners is simple: seek out reading and listening material we find compelling and comprehensible, then consume enough of it until we’ve internalised the language. If we get enough comprehensible input appropriate to our level, our comprehension skills will consistently improve and our ability to speak the language will then gradually emerge.

The online language learning community is full of influencers and learners – myself included – who have been inspired by Krashen. The likes of Steve Kaufmann and Matt Vs Japan (who I interviewed for this podcast) are examples of what can be achieved when Krashen’s principles are applied successfully.

But Krashen is not without his critics and there are question marks over how applicable his ideas are to learning Mandarin. Can Mandarin pronunciation and tones be acquired through comprehensible input alone or is in necessary to learn rules, use rote memorisation and repetition drills to become proficient? And what about grammar? Can we acquire Mandarin to a high level without deliberately studying grammar rules?

In this episode I want to take a critical look at the input hypothesis. To do so I’ve invited two Mandarin learning experts, both of whom have appeared on this podcast before. Professor Karen Chung is a linguist with decades of experience working at National Taiwan University. Daniel Nalesnik is the founder of the leading flashcard website Hack Chinese. Together we explore the strengths and limitations of the input hypothesis in the context of learning Mandarin.

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3 Thoughts

  1. Yikes. This podcast episode’s criticism of Krashen and CI felt pretty indicative of a lack of understanding of his theory, in addition to a lack of understanding of SLA overall. Especially the parts about not CI not leading to understanding grammar. You do not need explicit grammar instruction to learn a language. Period, full stop. The whole point of comprehensible input (which is not called “comprehensive input”, despite what one of the guests repeatedly said throughout the show) is that you pick up on the grammar patterns through the language presented to you, “i + 1”.

    My first ever Chinese class was 100% CI. We could go into the textbook and look up the explanations if we wanted to. We would all open our textbooks after class, glance at the grammar stuff and say “oh, well this is a pointless waste of study time. We already learned it all in class”. The teacher provided the correct input in the correct amount at the right time. There was never a need to look up grammar. Ever. The criticism that you won’t have a “language parent” to guide you in that way of learning only justifies the Chinese teachers out there that only ever explain grammar using the L1 of the people in the class. I’ve had over 40 Chinese teachers in the past 9 years and the only one that ever taught effectively was that first one, the one who used CI. The rest were mostly wasting my time or lighting a fire under my butt by forcing me to study long lists of irrelevant vocabulary, but “at least I was working on my Chinese”(??). For three years I actually lost a lot Chinese I had previously learned because the teachers were so against anything but grammar explanation and never provided any input outside of the dialogues from the one textbook. I know that’s not what you’re saying in this episode, but by suggesting that you can’t learn Chinese with CI, you’re only justifying the mindnumbingly bad methods that are prevalent in 99.9% of Chinese language classrooms around the world. And people wonder why everyone says “Chinese is hard”. No it’s not, and CI is a quick and easy way to prove it. You learned your L1 through input, why would your L2s be any different? I never needed to know English grammar until I majored in linguistics in college, why should I know Chinese grammar in depth before I reach the same level of linguistic aptitude? (ACTFL-Superior rating in Mandarin on the OPI and WPT and an “understanding” of Chinese grammar only hindered my process of getting there).

    As for tones and all the other things that this episode says “can’t be learned” through CI, once again, that’s only because you didn’t take the time to learn what CI actually is and how it is used before saying so on this episode. If you are getting sufficient input that is just above your level, you do not need explicit tone instruction, just as you don’t need explicit grammar instruction — that would be part of the lesson you are given. The teacher might ask you a question, you answer with the wrong tones, and the teacher would correct you. There’s no need to be screeched at by a self-important Chinese speaker who wants nothing more than to “put you in your place” by picking apart every aspect of your incorrect Chinese. That was my experience in Beijing and yeah, my Chinese got a little better, but it made me really HATE my teachers with every fiber of my being. I know I’m not a minority when it comes to experience with Chinese teachers that won’t tolerate errors getting the way of enjoying anything about learning.

    Comprehensible input does teach reading and writing, in addition to speaking. The fact that this was a criticism of Krashen really made me cringe. Where does Krashen imply that you never cover reading and writing with CI? Certainly TPRS covers reading and writing, in addition to presentations, putting on skits, etc.
    Even if that wasn’t created by Krashen, it’s still CI.

    Children do NOT have a better capacity for L2 learning; they know less language in their L1, so learning the same minimal amount of language in an L2 is no problem. Adults, especially adults who have attended higher education, feel like idiots for not being able to express themselves in an L2 as well as they can in an L1, so up goes the affective filter. Also, Children in an L2 environment are usually in school in the L2 for 6-8 hours a day, 5 days a week. They they go play with their friends in the L2 as well. Adults usually go to a language class for, even for an intensive, 20 hours a week. Usually it’s more like 2 hours/week, if that. To have anyone trying to talk about biological reasons for why children are better at learning languages or that “adults can’t learn languages as well as children” without acknowledging the conditions of the environment (children have waaayyy more opportunities to learn alongside their peers, who are also learning the language even when it’s their L1) shows a lack of consideration for one of the most basic reasons why “it’s hard to learn a language as an adult” — you don’t have nearly as many opportunities to interact with the language in a meaningful way as the children! That’s kind of like…not having comprehensible input.

    Adult learners do not learn better when information is handed to them. Lazy learners like to have rules given to them so they can move on to the next thing more quickly without putting in effort. Deriving the rules for yourself leads to far more meaningful connections and allows one to learn from their mistakes. Spoon feeding information to learners before they’ve had a chance to really struggle with it is no different than giving grammar lessons about the L2 using L1 in lieu of providing meaningful input. It is the difference between “being taught” something and “learning” something.

    I could go on and on about how frustrating this episode was, but I think I hit my main points. When it comes to language learning, especially Chinese learning, saying “it’ll never work because…” and backing that up with “practicalities” instead of proven research is always a bad idea. It’s even worse when all three people talking have missed most of the point of Krashen’s research and one guest doesn’t even know what comprehensible input is called. It worries me that all three people on this show are involved in language education. I became a language teacher because so many of my language teachers failed to meaningfully teach me the language they were supposed to teach. I want to make sure the next generation does not suffer as I did. I spend a lot of time reading up on methods and research and then immediately applying it in my classroom, usually to great success. Too much of what was said in this episode indicates a lack of understanding of SLA, especially for Chinese language education and for adult learners.

    tldr: If you’re actually using CI the way that it was intended, it is an excellent way to learn Chinese. You just need to find a teacher that’s trained in and willing to use it. Or teach your teacher how to use CI to teach you. If done correctly, you will learn Chinese way faster and effectively than any other method out here.

    1. Hello Katie, thank you for your in-depth response. I’ll address some of your main points in turn:

      “You do not need explicit grammar instruction to learn a language. Period, full stop.”

      – What evidence to you base this assertion on? I’m sure lots of grammar can be internalised through comprehensible input alone without the need for explicit instruction or other non-CI methods such as memorising lots of example sentences (sentence mining). But that’s not the same as saying that all grammar patterns can be internalised by everyone through comprehensible input alone. That’s an extreme view which requires strong evidence to support it and I haven’t seen any such evidence. Perhaps you can refer me to the relevant literature?

      “…by suggesting that you can’t learn Chinese with CI, you’re only justifying the mindnumbingly bad methods that are prevalent in 99.9% of Chinese language classrooms around the world.”

      – That’s why I suggest the opposite. In my experience comprehensible input is very effective. After two years of getting nowhere, discovering CI finally enabled me to progress to an intermediate level of comprehension. As I mention in the podcast I would have given up with out it. But the more I progressed the more I began to realise that it is NOT a magic solution to everything, as is often suggested.

      “When it comes to language learning, especially Chinese learning, saying “it’ll never work because…” and backing that up with “practicalities” instead of proven research is always a bad idea…”

      – I am broadly sympathetic to this view. But where is the “proven research” for the claims you’re making? Remember, extraordinary claims require extraordinary evidence. You claim the only thing that is needed to become proficient at Mandarin pronunciation and grammar is CI. That might be true but it is an extraordinary claim which contradicts every anecdotal piece of evidence I’ve ever seen. Everyone I met who has good pronunciation used additional methods and did not exclusively rely on CI. Those who exclusively relied on CI to get good at pronunciation speak with poor tones (often they are unaware of it as I was in the past before I mended my wayward tones). That doesn’t mean your statement is false but it certainly means the burden is on you to provide evidence for such a seemingly unlikely and counterintuitive claim.

      Overall I tend to find the lightest criticism of Krashen and CI tends to elicit disproportionately strong reactions. This podcast was broadly supportive. But CI is not a law of physics the way the tone of your response seems to imply. It is a hypothesis that should be constantly open to criticism and questioning.

  2. Blake Gross says:

    I didn’t hear many if any critiques of the Input Hypothesis in this episode. What I heard was a lot of criticisms of other aspects of immersion learning. The Input Hypothesis being more strictly what Krashen put forward as a theory, and immersion learning being the system of learning that favor immersion in native language content over outputting or explicit study.

    To start with Krashen,
    Krashen does not say:
    1) Output is detrimental to learning, in fact he strongly believes that output is a great way to get input (i+1), and this is personally how he learned languages
    2) Courses are useless (moreso that courses need to tend towards comprehensible input, which my first Chinese class did and was very effective at getting students speaking basic sentences)
    3) Everything can/only should be learned through input.

    What the Input Hypothesis is saying is that language acquisition comes from comprehensible input. Why this is “radical” is that it upended previous theories as to how to acquire a language, namely that language learning is axiomatic (i.e. words + grammar = speaking ability), a general 20th century trend of education.

    The hypothesis is basically that this is the reason that school children around the world go to language class and end up not having almost any ability in the language after years of study.

    In the episode, it seemed like everyone actually broadly agrees with everything above for the most part.

    Now, the wider immersion learning community has taken the Input Hypothesis as a basis, and made their own extrapolations based on it, a lot of which seemed to be objected to in this podcast.

    1) Output is antithetical to learning- This belief is not dealing with the input hypothesis, as much as it is dealing with a few different factors.
    – Being output centric slows down learning velocity
    – Output centric can compound mistakes (phonetic and sentence pattern)
    – Most people you have opportunity to output with are non-natives, this in short bursts can be helpful, but long term can make it so you all are compounding similar mistakes. It’s also rare to have learners at the same level.

    For most learners, it’s not necessarily practical not to output for various reasons (lack of motivation, necessity, etc). The point is moreso, input > outpout.

    2) Tone acquisition can only happen from input – It’s certainly naively true that tone acquisition can happen from input alone. In fact, I think it would probably be impossible for someone to learn Chinese without tone acquisition. However, as pointed out, input alone obviously is not the most effective way to learn tones. Like I said above, the Input Hypothesis certainly doesn’t say explicit study of characteristics of a language, esp phonetics, isn’t effective. A lot of the immersion learning community puts particularly heavy emphasis on phonetic study through deliberate practice and not input alone, esp for output. So I’d say that the idea that tones should be explicitly practiced/learned in Mandarin are in line with everyone’s thoughts.

    3) “Language parenting” as a necessity – I heard this be brought up, that someone would need every mistake corrected like a mother corrects their child as a mechanism of learning. This is a misnomer. Parents don’t actually correct their children much in practice. It seems to be that children fix their mistakes over time naturally.

    4) Explicit grammar study is anti-input- This is another misnomer. Input Hypothesis is not anti-grammar. It’s anti the idea that grammar + words = comprehension. Most immersion learning communities put grammar overview up front as a mechanism for being able to comprehend the language. I’d say the difference is that grammar study is usually considered more of a cursory thing to study to jump start input, and that grammar drills are seen as not effective. Anecdotally, I’ve found that to be true. Learning about grammar is helpful in comprehension, but drilling the grammar does next to nothing for actual ability to output. This is partially due to the problem of what I call, “soft grammar”, which is that non-hard language rules determine a majority of real speech (i.e. language output really that creative), so it’s very difficult to know when to naturally apply an axiom. Regarding 1T mining, I think this is a really effective technique to learn natural sounding speech. I wouldn’t call this learning hard grammar though, I would call this learning soft grammar, which is the way the language is actually used.

    Some criticisms:
    1) Daniel mentioned at one point that watching or listening to something that he didn’t understand was not fun and felt like a waste of time, as an objection to immersion learning. I would say that input hypothesis and immersion learning tends to agree with his feeling that it would be a waste of time. There is some benefit to watching or listening to incomprehensible content (such as working on what can be picked out), but the less i+1 that exists, the less useful it becomes. This is why graded readers are so useful for early learners.

    2) Feedback needs externalities – You mentioned tone mistakes needed a tutor to correct. I think that is a good thing, I don’t think that necessarily contracts the input hypothesis either. I don’t think the input hypothesis states that phonetics can be acquired for production using only input. I also think that chorusing can likely eliminate tone mistakes without the need of a tutor, but without a native speaker validating, it will be difficult to know if it’s right.

    3) Explicit grammar instruction- I strongly disagree that this is needed. Otherwise every native English speaker would confuse a/the. The issue is that people are not either immersing enough or getting feedback. The SVO/SOV flip to Chinese is also covered in classes and grammar study, so I’m confused about the example here. I learned very early on about the 把,将 flip. Also, immersing in literary Chinese will necessitate that learners understand topic-comment structure. We do subconciously monitor speech, but we do not subconciously monitor grammar patterns. At the end it was mentioned that it would be impossible to learn Chinese without explicit study due to how much emphasis is placed on reading/writing in Chinese. I agree that not learning how to read in Chinese is a huge handicap for learners, but certainly people were speaking Mandarin pre-CCP literacy movements. There are many Chinese topolects that are not written as well that are likely just as phonetically limited that likely have no explicit grammar study.

    4) Writing is not important- It’s just not. I barely write in English, I’ve forgotten most of cursive. Writing is important as a skill for situations where it would be useful (like living in China), but there is way too much emphasis put on it. Stroke order is important for character lookup really.

    1) I do agree that being conscious of tones is helpful, esp when speaking. However, I think that there is a tendency to over emphasize explicit tones rather than overall phonetics. It’s probably more effective to mirror for phonetics that anything. I think you are right about Krashen being wrong here.

    2) Critical Age hypothesis- I think there certainly are neurological differences in child language learners. There is a lot of evidence as well that bi-lingual children/adults have an easier time acquiring additional languages. I naively have to believe that the importance of language to the brain necessitates that there is neuron rigidity to that. I like how Karen brings up that actually adults have an easier time, because they are more cognicent (though I disagree that this means explicit grammar study is that useful). Certainly immersion learners are studying though, they aren’t just letting it flow through them. When I watch a show I pause at every sentence I don’t understand to make sure I understand it before moving on.

    Overall, I think there was an interesting discussion with some good learning tips, but I’m not sure there was really critique against the Input Hypothesis. The largest critique against the Input Hypothesis is that it’s not been widely tested and reproduced which makes it more of a soft than hard theory still. I also agree that Krashen’s German experiment is fun to show, but a bit of a weak evidence due to what was mentioned.

    Love the idea of an immersion weekend.

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