The Input Hypothesis is part of a group of 5 hypotheses related to Second Language Acquisition developed by the linguist Stephen Krashen.
According to this Hypothesis, the results of the acquisition of a second language are related to the input that the acquirer receives/is exposed to. However, this input has to be understood (comprehensible input), and it is from this precept that Krashen established that in order for the acquirer to achieve results, the level of language he is exposed to must follow the i + 1 standard where i means the Acquirer’s actual competence in the language and +1 means a bit further. That is, the students should always be exposed to a slightly more advanced level of understandable input so that they can achieve ever more fluency in the Second Language.
Based on how children acquire their first language and the caretaker speech (a simple language used with children for them to understand), Krashen proposed something similar to be worked on with adults: the teacher-talk, the Foreigner-talk, and the Interlanguage- talk, also known as Simple codes.
The “Teacher-talk” is the classroom language that accompanies exercises, the language of explanations in the second language and in some foreign language classrooms, and the language of classroom management. “Interlanguage talk” is simply the speech of other second language acquirers, often that of the foreign student peer group and “Foreigner-talk” may be of two kinds. The term has been used to describe native speakers’ imitations of second language speech or, rather, their acquisition of aspects of this interlanguage. (Krashen, 1981,p. 121)
According to him, these are the 3 simple codes that are part of the process of acquiring a language. The teacher-talk promotes more input than the exercises a teacher may do in classes. So, the language itself used in the teacher speech is a way of promoting comprehensible input, that is if the teacher takes into account that the language, he may use, must be into the patterns of the formula i+1 cited above. The theorist also mentions the interlanguage-talk and the foreigner-talk that provide the students with the input they need during the classes and outside the school environment.
In sum, this hypothesis says that we acquire language through a unique way, comprehending or receiving comprehensible input and that this comprehension follows a natural order, from i to i+1. So, an input is an essential ingredient in Language Acquisition and is related to other 4 Hypotheses.
By M. A. M. Júnior
REFERENCES
KRASHEN, Stephen. Second Language Acquisition and Second Language Learning. University of Southern California. Available on: <http://www.sdkrashen.com/content/books/sl_acquisition_and_learning.pdf> Access on
KRASHEN, Stephen D. Issues and Implications. In: The Input Hypothesis. 1985. p. 1-32. Available on: <https://www.uio.no/studier/emner/hf/iln/LING4140/h08/The%20Input%20Hypothesis.pdf> Acess on
Stephen Krashen. In: Wikipedia, the free encyclopedia. Available in: <https://en.wikipedia.org/wiki/Input_hypothesis#cite_note-Krashen2003-3> Access on Nov 30, 2018.
Krashen's Second Language Acquisition Theory 