"Interactions do not necessarily lead to immediate understanding. Rudimentary understandings must be developed and refined over time, often through misunderstandings." (pg. 63).

Short summaries of each hypothesis:

The Acquisition/Learning Hypothesis: Language can be acquired naturally through meaningful interactions and communication. Acquisition is more effective for fluency rather than learning.

The Monitor Hypothesis: Language learners use their conscious knowledge of grammar and rules to check and correct their speech or writing. However, this "monitor" acts as a tool rather than the main way language is acquired.

The Natural Order Hypothesis: Language structures are learned in a predictable sequence such as simple grammar before the more complex grammar This order cannot be changed by instruction.

The Input Hypothesis: Learners acquire language when exposed to comprehensible input that is language slightly beyond their current level or i+1. Exposure to a slightly challenging language is the best way to acquire a second language.

The Affective Filter Hypothesis: Emotions like anxiety, motivation, confidence, and self-esteem affect language learning. Teachers and environments that reduce anxiety and encourage confidence help learners acquire language more effectively.