The Monitor Hypothesis in Second Language Acquisition

The Monitor Hypothesis is one of five hypotheses developed by the linguist Stephen Krashen.

  1. The Acquisition-Learning hypothesis
  2. The Monitor Hypothesis
  3. The Natural Order Hypothesis
  4. The Input Hypothesis
  5. The Affective Filter Hypothesis

The monitor hypothesis asserts that a learner’s learned system acts as a monitor to what they are producing.

In other words, while only the acquired system is able to produce spontaneous speech, the learned system is used to check what is being spoken.

Before the learner produces an utterance, he or she internally scans it for errors and uses the learned system to make corrections.

Self-correction occurs when the learner uses the Monitor to correct a sentence after it is uttered.

According to the hypothesis, such self-monitoring and self-correction are the only functions of conscious language learning.

The Monitor model then predicts faster initial progress by adults than children, as adults use this ‘monitor’ when producing L2 (target language) utterances before having acquired the ability for natural performance, and adult learners will input more into conversations earlier than children.

3 Conditions to Use the Monitor Hypothesis

According to the Monitor Hypothesis by Krashen, for the Monitor to be successfully used, three conditions must be met:

  • The acquirer/learner must know the rule: This is a very difficult condition to meet because it means that the speaker must have had explicit instruction on the language form that he or she is trying to produce.
  • The acquirer must be focused on correctness: He or she must be thinking about form, and it is difficult to focus on meaning and form at the same time.
  • The acquirer/learner must have time to use the monitor: Using the monitor requires the speaker to slow down and focus on form.

Monitor Hypothesis: 3 Types of Users

Monitor Over-Users: These language learners are too concerned and focused on correctness that they can’t speak with any real fluency. Some characteristics of monitor over-users are:

  1. They know many of the rules of the English language
  2. They are not able to communicate in speech
  3. Their written English might be quite accurate
  4. They don’t have speaking fluency because they are too concerned with being grammatically correct
  5. When speaking, these language learners make many pauses, repetitions and speech repair.

Monitor Under-Users: These language learners are not focused on correctness because they have not consciously learned the rules or because they have decided not to use their conscious knowledge of the target language. Some characteristics of monitor under-users are:

  1. They don’t use the monitor under any conditions even when they have the opportunity
  2. They don’t use conscious linguistic knowledge in their speaking performance
  3. These learners aren’t able to correct their own errors in written English
  4. These students might not like grammar
  5. They believe that grammar rules are important but hardly use when they speak
  6. These learners tend to rely on instinct to spot errors in their second language performance
  7. These students are not embarrased to make mistakes

Optimal Monitor -Users: These language learner are able to keep a balance between self-correction and fluency so error correction is not an obstacle in their quest of communication. These learners use their knowledge appropiately. Some of the characteristics of these users are:

  1. They have fluency and accuracy when they speak or write.
  2. These learners are able to correct errors and mistakes in their own language performance.
  3. They know the rules and use them when they communicate

Monitor Hypothesis: Difficulties Using the Monitor

There are many difficulties with the use of the monitor, making the monitor rather weak as a language tool.

  • Knowing the rule: this is a difficult condition to meet, because even the best students do not learn every rule that is taught, cannot remember every rule they have learned, and can’t always correctly apply the rules they do remember. Furthermore, every rule of a language is not always included in a text nor taught by the teacher
  • Having time to use the monitor: there is a price that is paid for the use of the monitor- the speaker is then focused on form rather than meaning, resulting in the production and exchange of less information, thus slowing the flow of conversation. Some speakers over-monitor to the point that the conversation is painfully slow and sometimes difficult to listen to.
  • The rules of language make up only a small portion of our language competence: Acquisition does not provide 100% language competence. There is often a small portion of grammar, punctuation, and spelling that even the most proficient native speakers may not acquire. While it is important to learn these aspects of language, since writing is the only form that requires 100% competence, these aspects of language make up only a small portion of our language competence.

Manuel Campos, English Professor

Manuel Campos

I am Jose Manuel, English professor and creator of, a blog whose mission is to share lessons for those who want to learn and improve their English