The Natural Approach, developed by Stephen Krashen and Tracy Terrell, is a language teaching methodology that emphasizes a communicative and holistic approach to language acquisition. The approach focuses on the development of language skills through exposure, comprehension, and meaningful communication rather than explicit grammar instruction. The Natural Approach addresses the four language skills—listening, speaking, reading, and writing—through distinct procedures. Additionally, it outlines four basic stages of Second Language Acquisition (SLA).

Procedures of the Natural Approach for Teaching Four Skills:

1. Listening:
   • Comprehensible Input: Provide learners with comprehensible input, which is language slightly beyond their current proficiency level. Teachers use gestures, visual aids, and other context clues to make the input understandable.
   • Listening Activities: Engage students in various listening activities such as storytelling, audio recordings, and authentic materials. The goal is to expose learners to natural language use and help them develop their listening comprehension skills.
   • Understanding Non-Verbal Cues: Encourage learners to understand non-verbal cues, expressions, and intonation to enhance their ability to interpret spoken language.
2. Speaking:
   • Silent Period: Acknowledge and respect the silent period, during which learners may choose to listen and comprehend before actively speaking. Allow students to progress to speaking at their own pace.
   • Imitation and Repetition: Encourage learners to imitate and repeat language patterns. Initially, students may engage in scripted dialogues or rehearse common phrases to build confidence.
   • Communicative Activities: Facilitate communicative activities that encourage meaningful spoken interaction. This can include pair or group discussions, role-playing, and language games.
3. Reading:
   • Comprehensible Input in Written Form: Introduce written texts that are comprehensible and slightly above the learners' current proficiency level. Use visual aids and context to support understanding.
   • Silent Reading: Promote silent reading for comprehension. Allow students to read at their own pace and encourage them to focus on understanding the overall meaning rather than decoding every word.
   • Storytelling and Narratives: Integrate storytelling and narratives into reading activities. This helps learners connect spoken language to written form, reinforcing language patterns.
4. Writing:
   • Imitative Writing: Start with imitative writing exercises where learners reproduce sentences or short passages they have encountered in spoken or written form.
   • Creative Writing: Progress to creative writing activities, encouraging learners to express themselves in the target language. Emphasize meaningful communication and focus on conveying ideas rather than strict adherence to grammar rules.
   • Feedback and Revision: Provide feedback on written assignments, emphasizing content and communication. Encourage learners to revise and refine their writing based on feedback.

Four Basic Stages of Second Language Acquisition (SLA) in the Natural Approach:

1. Preproduction (Comprehension):
   • Characteristics: Limited verbal production, focus on listening and understanding.
   • Activities: Listening to comprehensible input, observing non-verbal cues, engaging in silent reading, and participating in non-verbal communicative activities.
2. Early Production (Early Speech):
   • Characteristics: Limited verbal production with short phrases, basic vocabulary use.
   • Activities: Participating in simple dialogues, practicing basic vocabulary, engaging in imitative speaking activities, and gradually progressing to more complex communication.
3. Speech Emergence:
   • Characteristics: Increasing ability to produce longer sentences, expanding vocabulary, developing more confident speaking skills.
   • Activities: Engaging in communicative activities, participating in role-playing and discussions, practicing storytelling and narratives.
4. Intermediate Fluency:
   • Characteristics: Advanced language production, improved fluency, ability to communicate in varied contexts.
   • Activities: Engaging in more complex reading and writing tasks, participating in extended discussions, exploring diverse language registers and genres.

These stages represent a developmental progression in learners' language acquisition journey, acknowledging the importance of exposure, comprehension, and meaningful communication in the language learning process.