Krashen's Five Hypetheses

1. The Acquisition-Learning Hypothesis

This hypothesis differentiates between two ways of gaining a second language:

Acquisition is a subconscious process, similar to how children learn their first language, focusing on meaningful interaction.

Learning is a conscious process, involving formal instruction, rules, and grammar.

Example: A student acquires a new word by hearing it repeatedly in context versus learning it by memorizing a definition.

 

2. The Natural Order Hypothesis

Language structures are acquired in a predictable sequence, regardless of the learner's age or first language. Some grammar rules (e.g., -ing in English) are learned earlier than others (e.g., third-person singular -s).

Example: Beginners may use “She running” before mastering “She is running.”

 

3. The Monitor Hypothesis

The "monitor" is the part of our mind that edits or corrects language output based on learned grammar. While helpful, overusing the monitor can slow fluency.

Acquisition provides the fluency; learning acts as a monitor.

Example: A student self-corrects saying "He go" to "He goes" during a conversation.

 

4. The Input Hypothesis

Language acquisition happens when learners are exposed to comprehensible input slightly beyond their current level (i.e., i+1). . Vygotsky’s zone of proximal development supports this hypothesis, where in students must go beyond what they already know and build their new understanding on that foundation

i = Current knowledge (initial knowledge, input)

+1 = New, slightly challenging language material

Example: A beginner understands “I am eating an apple” even if they are unfamiliar with the word “apple” because of the context.

 

5. The Affective Filter Hypothesis

Emotional factors like motivation, confidence, and anxiety influence language acquisition. A "high affective filter" (e.g., stress, fear of mistakes) can block input, while a "low filter" fosters learning.

Example: An anxiety-free student in a friendly environment is more likely to acquire language than one who is anxious or pressured.

 

Implications

Use examples and activities that illustrate each hypothesis. For instance:

Acquisition vs. Learning: Engage students in storytelling or role-play to emphasize acquisition, in addition to grammar drills that emphasize learning.

Input Hypothesis: Use graded readers or videos with visuals to provide comprehensible input.

Affective Filter: Create a supportive, low-stress environment in class.