February 4, 2019
Terry Waltz

On the surface, this idea sounds simple. Input is stuff coming in. For a language class, that means students are hearing or reading something. Language goes into their ears or eyes, to their brains, from the outside.

And “comprehensible,” according to the Oxford English Dictionary, means “able to be understood.” Comprehensible Input is incoming language that can be understood.

Why do we care about Comprehensible Input in the first place?

We care because SLA (second language acquisition) research tells us that hearing or reading Comprehensible Input (abbreviated as “CI”) is what makes people gain proficiency in a language. It is the way all babies learn their first language—by understanding the language they hear.

Clearly, there are some important differences between our students and babies. Babies have nothing better to do than listen to what’s going on around them and try to figure out what it means. No one is grading them. They are not under stress while learning this amazing communication tool—a tool they can immediately put to use and which they are roundly praised for using, even when they make mistakes.

School-aged students are in a different situation. They know more about more things. They can understand concepts more easily. However, schools, parents, and other stakeholders are expecting greater Rigor, at earlier and earlier grades, from educational programs. The simple joy of understanding or being understood is not considered “enough.” Rarely is a real result linked to language used in a school setting. The student in school may barely get a nod for a correct answer before the teacher moves on to the next student.

For many years, Rigor in education meant analysis. “Language class” meant Latin or Greek, languages not intended to be spoken, only read and painfully translated. One simply “picked up” other languages, such as from a French-speaking governess. When other languages did become school subjects, they were pushed into the same grammar-centric mold as the classical languages. The CI that helped people “pick up” languages in the past was thrown out in favor of analysis and explanations. Of course, there was some language input that was understood by students. Some of the students had a better natural understanding ability, and gained more from it. Most students taught a foreign language with this system graduated and, as the Chinese say after cramming for and completing a big exam, “returned the content to the teacher.” It simply exited their brains, and they had little or no language proficiency as adults, despite the years of class.

It is a myth that few people are “good at” foreign languages. Every person acquires a first language with no instruction at all. That’s where native speakers come from, and there’s no one better at a language. The big change is not to people’s brains but to the environment provided. For the first language, the environment was full of positive support and interesting messages the child could understand. Older students aren’t lacking the ability to acquire a second (third, fourth, etc.) language, only the CI that would allow their brains to do it.

The good news is that organizations like ACTFL are now recognizing the importance of providing CI in the language classroom. There’s an emphasis on real communication: messages students want to understand, instead of repetitious, manipulative practice sentences about some guy in a textbook named José that no one knows or cares about. The more language we speak that students care about and understand, the more acquisition will happen, and the better students will be at the target language.

That understanding is crucial, because we acquire language by matching meaning to incoming speech (or text we are reading, but let’s just think about oral language for now). We have to understand the speech we are hearing in order to acquire it, because it is matches between sound and meaning that cause pathways to develop and become stronger and faster in the brain. If we do not have meaning to match to the incoming language, it is just noise. Miraculously, the matches happen unconsciously. We only need to focus students on the meaning of what’s being said—not the way it’s said, the words used, or the fact that hablar is an -ar verb being used in the third-person singular preterite. Their amazing brains handle the acquisition without anyone needing to do anything more, as long as there’s Comprehensible Input coming in and being comprehended.

Most K-12 teachers say there are not enough class hours in a year to do everything they want to do with their students. As teachers, we need to make every minute count. If we believe language is acquired through CI, by matching meaning to messages coming at the student, we want to focus on providing CI that students not only can understand but really DO understand.

This is important: we need input the students understand, not input they could understand if they just guessed a little, not input they might be able to work out, given a few minutes to discuss a sentence in groups, see it in writing and draw diagrams, refer to a verb chart, or whatever. The understanding has to come quickly. Too much delay between hearing language and understanding the meaning and the sounds will no longer be in working memory to match the meaning to. We need to make the best use of our impossibly limited class time, by maximizing the amount of CI we give students in that golden window when the sounds are still in their memory.

The point of providing CI is to facilitate instant matches between language and meaning. When there is understanding, it’s as though there is a bucket in the brain for each word, grammar pattern, word ending, and every other little piece of language. Imagine each time there is a match between meaning and sound, a row of clerks in the student’s unconscious mind adds a single drop of water to the bucket each is responsible for, but only if the piece of language corresponding to that bucket was heard and matched. The conscious mind doesn’t need to bother about this. The conscious mind just deals with the big picture. If the input is “Look! A dancing panda!” the conscious mind only sees a cavorting animal, but the unconscious mind says to itself, “I hear an -ing, and that means the action is ongoing. A drop of water for my bucket!” The unconscious mind cuts the meaning up into little pieces and matches it to incoming sounds, and gradually fills all those buckets. Some buckets fill quickly, while others take more time. When a bucket is full, the water can spill out the top without any effort at all, and the student can easily and correctly output that language without having to even think about it. It has been acquired when the “bucket” is full.

If the input is not comprehensible, the clerks with the buckets are stymied. “I know I have heard that -ing sound on the end of words, but I have no idea what it means. I cannot add a drop to my bucket!” When they cannot understand, they cannot do their job, and they become frustrated. If they are frustrated long enough and consistently enough, they give up. “I will never know the meaning of what I am hearing. Why bother?” This is also what students do. Students getting input that is not comprehensible often engage in “undesirable student behaviors.” Many “management issues” improve when the teacher slows down and makes sure students can understand what is being said in the target language. The input must be comprehended by those students in front of us, not just be potentially comprehensible.

For students to understand language, at some point they have to be shown or told what the language means. With concrete things, this can be easy. “Ball!” “Banana!” “Dinosaur!” It can be difficult when things get more complex. Pointing to the “ceiling” could be misinterpreted as pointing to a light, the sky, or just “up.” While many teachers like to use realia, pictures, gestures, or mime to show students what language means, there’s also another powerful and efficient means available: students already speak one language, use it to tell them what the new word means. Just like that, you have comprehension in very little time.

The great thing about CI is that we can use it no matter where we are in our teaching journeys. We can add it to every situation and activity in our classrooms, even if those activities were not specifically designed to provide CI. There are many resources available today to help teachers design their instruction from the perspective of making the language comprehended by their students. Why not pick five minutes of class time today and think carefully about whether, during that time, your students—the actual ones in front of you, at whatever place each one is in their personal journey to fluency—can understand you or not?

Posted By Terry Waltz  

Terry Waltz can get herself into trouble in a dozen or so languages and back out of trouble again (with luck) in three. You can find more of her writings on CI at terrywaltz.com.

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  1. I agree that comprehensible input is essential for students to be able to learn. As a 1-5 Spanish teacher, I believe it is my job to help students become used to hearing the language and making sense of it, in preparation for their journey to proficiency in the language. All the “clues” (or CI) I give them help their brains grow! That is why it is so sad that there are fewer K-5 FLES programs every year.

  2. Well put! This will help other teachers, parents and students understand.

  3. Yes!! This!

  4. There is noticeably a bunch to realize about this. I assume you made various good points in features also.

  5. I appreciate you sharing this blog article. Much obliged.

  6. Thank you for such a fantastic blog. Where else could anyone get that kind of info written in such a perfect way? I have a presentation that I am presently working on, and I have been on the look out for such information

  7. Great post Terry! You so eloquently put into words exactly what I try to convey to parents about how people acquire a second language!

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