According to Second Language Acquisition (SLA) theory, developed by Stephen Krashen, the way humans acquire languages is through receiving input, usually aural, that is understandable; this is termed ‘Comprehensible Input’ (CI). Think, for example, of a parent talking to their child: when they ask the child, ‘Do you want milk?’, the milk is visible, tangible. The child understands that they are being offered milk. Parents don't just say this once, they offer it hundreds, even thousands of times. According to this hypothesis, the input (the parent talking) is comprehensible (the child understands it); the brain is trained to automatically make meaning.

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开始使用 CI 进行教学

根据 Stephen Krashen 提出的第二语言习得 (SLA) 理论，人类习得语言的方式是通过接收可以理解的输入，通常是听觉输入；这被称为“可理解输入”（CI）。例如，想象一位父母与他们的孩子交谈：当他们问孩子“你想要牛奶吗？”时，牛奶是可见的、有形的。孩子明白他们正在被提供牛奶。父母不只是说一次，他们提供了数百次，甚至数千次。根据这个假设，输入（父母说话）是可理解的（孩子理解它）；大脑被训练自动产生意义。