Revisiting Input and Output Hypotheses in Second Language Learning

This article discusses the impact that both input and output hypotheses have on second language learning. For decades, there have been opposing ideas in this regard. Several studies were consulted to have a clearer view of which approach is more recommendable for people involved in language teaching. For several years teachers of second language strongly believed that learning a new language depended on the exposition of learners to the target language. For effective learning, the exposition should be higher than the students’ level but comprehensible enough for them to understand. However, this hypothesis was rejected when a new study revealed that the exposition was not enough. Students need to use the language they have learnt. These new ideas emerged from the output hypothesis that had a significant impact on the field of language teaching. The article concludes that both approaches can be used complementarily although more study is still needed.


Introduction
For a long time teaching second languages has always tried to replicate the different factors that play major roles in first language acquisition without being completely successful.During centuries, translating texts from Latin and Greek into a target language was a heavy and boring task.Those activities were far from being communicative because at that time, that was not the main objective.When communication among people of different countries and cultures became paramount, such as in wartime, new methods and approaches to teaching languages appeared.Some of them, such as Audiolingualism -which was based on a convincing theory of learning (Behaviorism) worked very well for quite some time (some drill techniques are still in use today) but due to the fact that many questions about language learning remained unanswered, linguists went beyond trying to find better principles and theories that provided a more satisfactory explanation to the how languages are learned providing the right techniques, strategies and conditions for a successful replication of this process.Many years have passed since the first theories were posited and there are still disagreements on what hypotheses better explain the learning of a second language.
In this article, Stephen Krashen´s input Hypothesis and Merrill Swain's Output Hypothesis will be reviewed in order to see if these two apparently contrasting views finally reconcile or they certainly represent two worlds apart.

Material Studied
Second language acquisition has always attempted to duplicate first language acquisition.But there are many elements that have to be taken into account, most importantly, that there are different scenarios for the acquisition process as a first or second language.As Schachter (1988) points out, it is not logical to make a comparison between a child´s first language acquisition and an adult´s second language acquisition due to not only physical differences but also cognitive and environmental differing conditions.Let us take the innatist point of view for instance: a child does not have to be taught at all, and yet the child ends up acquiring the language he has been surrounded by.Why is this so?According to the innatist theory everyone as a child is biologically programmed for language acquisition in the same way other biological functions develop such as walking.So this innate ability would allow all children to acquire with ease the language that their environment supplies them, unlike grown-ups who have developed language awareness and tend to question everything linguistically speaking, believing that by understanding how a foreign language works in terms of its syntax and morphology, they will be able to assimilate it and produce it.Despite these and other differences, successful second language acquisition by grown-ups is a reality (of course putting aside obvious marked differences between natives and successful non-natives such as accent, fluency, vocabulary and accuracy) and theories account for that.Stephen Krashen's Input Hypothesis (1985) claims that language acquisition takes place when a person is exposed to sufficient comprehensible input, being this the only cause for it.If input is comprehensible and constant, speech will finally emerge.This input, according to Krashen, has to be slightly ahead of a person´s present knowledge of grammar.This is outlined as i + 1 in his theory and this the way a learner can get something new, otherwise if a learner is presented with language and patterns that he already knows, this would result in useless input and acquisition would not take place.In terms of grammatical elements, in Krashen's view, this would be automatically provided by the right amount of input and as long as this is understood.
Though Krashen´s hypothesis sounds appealing and we cannot question the importance of input to language acquisition, it certainly leaves several issues unresolved.When he indicates that speech will "emerge", he does not clarify that this emergence of language may depend on how highly motivated, extrovert, smart and conscientious learners they are.For the introvert, less bright, unmotivated and anxious students, language might not emerge for a long time or if so, it might emerge in an unsuccessful fashion.Krashen also tells us that the learner has to be exposed to sufficient input but does not indicate how much exactly or how people can know what sufficient is.Another issue to keep in mind is that Krashen does not tell us what comprehensible means exactly.Michael Long (1983) might shed some light on this by stating that input can become comprehensible when this has been modified or simplified.
As the input hypothesis did not seem completely satisfactory to answer those unresolved matters, there were some scholars and linguists who had different opinions on this matter.One of them was Merrill Swain.Swain had been studying children's second language acquisition in a Canadian French immersion program.She observed that in spite of being exposed to years of comprehensible input, students in these programs were significantly weaker in the productive skills than in the receptive skills.This led her to think that input was not the only element that plays a significant part in language acquisition and that verbal production was also needed in order to enhance accuracy and fluency in SLA.According to Swain's Output Hypothesis (1985) when learners come across difficult situations to get their messages across, they tend to make a more considerable effort to achieve this goal appropriately.Students, therefore, need to be pushed or stretched in their output.In other words, students have to make themselves understood by either modifying their utterances or using forms that they had not used previously.We can certainly agree with these Input and Output proposals and acknowledge the importance they have in acquiring a second language but one wonders how input alone can achieve the command of a language if we do not have the opportunities to put what we have acquired into practice and without having the proper feedback.If evidence shows (Swain's study) that input-besides being comprehensible-does not accomplish successful writing and speaking skills in learners, there seems to be that something is missing and Krashen's theory would be incomplete.On the other hand, comprehensible output which has been defined by Swain as "a message conveyed precisely, appropriately and coherently", strives for something that is what any second language acquisition learner wants to achieve, which is the conveying of a message in a clear and precise way.But this cannot occur unless we have the right input, language model and feedback in order to succeed.Krashen (1998) claims that comprehensible output is not really conducive to developing linguistic competence because of the following 3 reasons: output is too scarce, it is possible to get high levels of linguistic competence without the presence of output, (according to his personal experiences) and most of all, because so far there has not had direct evidence of output leading to language acquisition.On the other hand, how can extra linguistic information make someone acquire, as Gregg (1984) stated," the third person singular -s or yes/no questions, or indirect object placement, or passivization" (grammatical knowledge) by just being exposed to language when this is understood at a level of "meaning" only?Two interesting situations can be observed in a linguistic exchange: 1) The fact that if a learner (especially a beginner) gets some input, there is a high chance that the learner cannot understand the message the other person is trying to get across, no matter how comprehensible this is, due to a number of different reasons such as lack of vocabulary, minimum previous exposure to the foreign language, low affective filter, etc. and 2) the learner might understand the message but that does not mean the learner is going to acquire the correct grammatical knowledge.This can happen because the utterance can be provided by someone who does not have a good command of the target language.If we take the famous sentence "Me Tarzan, You Jane" the learner may understand the message but the learner is unlikely to grasp syntactical or grammatical knowledge from a sentence like this.Actually, by understanding the message, little knowledge, apart from knowing the meaning of words and body language (If it is a face to face interaction) is needed in an exchange like this.But if the learner wants to communicate something in a meaningful and unequivocal way, this would force him/her to develop a higher syntactic processing which can only be done by language production or output.

Results
The studies reveal that language acquisition is different from second language acquisition.First, the mother tongue is acquired spontaneously and in a natural form since we are born.On the other hand, second language is usually learnt after the mother tongue has been acquired.It is usually learnt inside a classroom which is an artificial context.Second, Krashen claims that learners acquire a second language if they are exposed to comprehensible input.Third, second language acquisition is incomplete if learners do not produce language coherently and clearly which is known as comprehensible output.Fourth, comprehensible output would depend on comprehensible input.The convergence of these four can help teachers understand how a second language can be acquired.

Discussion
After the analysis of both theories, it seems that both Input and Output Hypotheses instead of clashing, they really profit from each other and far from being distant from one another they appear to be closer than they seem.
It has been said that Krashen talks about Comprehensible Input but he fails to explain to us how input can be comprehensible.He claims that it can be made comprehensible by providing meaningful, contextualized messages.Long (1983) agrees with Krashen in the fact that for language acquisition to take place, input is completely necessary but he goes further by stating that if input is not comprehensible, this could be so by modifying the interaction with other speakers.It is a reality that beginner -level learners are highly unlikely to acquire a second language by interacting with native speakers who only use native talk.What happens in this kind of interaction is that natives usually modify their speech by using "foreigner talk", rephrasing, clarifying requests, checking comprehension or resorting to any other strategy to make their "native input" comprehensible.If the output comes from the learner and is not comprehensible, the listener can start negotiating for meaning so they can get to a point in which understanding is achieved.Swain (2000) considers this interaction as a collaborative dialogue, stating that second language learners, by taking part in production tasks, co-construct linguistic knowledge.Output and production then are the other key components to complete the whole mechanism.As a final example, we can take the case of Jim, a child who was deprived of human conversational interaction because his parents were deaf and his only input was the TV.During his first 3 years, his only contact with oral language was television.Jacqueline Sachs (1981) studied Jim´s case and when he was given an oral assessment at the age of 3 years and 9 months, it was detected that he was way below other children his age in all aspects of language.When he tried to express ideas appropriate to his age, his utterances contained ungrammatical and unusual order.When he was 4 years and 2 months, after some time he spent engaged in conversational sessions with an adult, he was already able to produce language typical of his age and the strange and ungrammatical patterns had disappeared.This shows that input, though comprehensible (TV= sounds, images, movement, colors, different topics, available anytime) is not enough, especially if it is something impersonal.The same might happen if the input comes from an Audio-based course and no human interaction is provided.The same could be said about an online language course that is practiced on a computer.As input is not sufficient to achieve language acquisition, this has to be supplemented with output in productive tasks.The study about Jim also shows that human interaction by means of negotiating and modifying language is crucial in a child's language.If this situation occurs in first language acquisition, this is also true in second language acquisition where there is a point in which the student needs to be guided or instructed by a teacher or interlocutor.

Conclusion
We can conclude that the Input and Output hypotheses seem to be more connected to what it seems.Comprehensible Input is a determining factor for a learner to assimilate language that can be on hold for some time until it finally emerges.This language emergence can occur or be accelerated when learners engage in productive tasks such as writing and speaking and even though this will not produce correct grammatical sentences at once, the constant exposure to language added to a frequent practice of it will finally do the trick.
In the meantime, linguists, theoreticians and scholars will continue dealing with new hypotheses that can help teachers and students achieve their corresponding goals successfully.