[blank_start]Acquisition[blank_end] involves the subconscious acceptance of knowledge when information is stored in the brain through the use of communication. [blank_start]Learning[blank_end], on the other hand, is the conscious acceptance of knowledge 'about' a language. Krashen states that [blank_start]the monitor[blank_end] is controlled by the learning system and is used to correct errors in the utterance. The [blank_start]Natural Order[blank_end] Hypothesis suggests that parts of language are learned in a certain sequence that cannot be altered through deliberate teaching. The theory that language acquisition occurs when learners receive messages they understand, known as [blank_start]comprehensible input[blank_end], is referred to as the [blank_start]Input[blank_end] Hypothesis. Different variables such as anxiety, self-confidence, motivation, and stress can all impact the [blank_start]affective filter[blank_end].