本文为《Second Language Acquisition and Second Language Learning》（二语习得与二语学习）一书结论总结。
本文是从实用的角度出发来说明我们在二语学习的过程中，各种方法的优劣，有哪些坑需要避免，有哪些错误的观点需要澄清，进而达到最好的学习效果；本文的侧重点没有放在二语学习的研究过程，我们注重的是结论，而且这些结论是被语言学习研究者经过试验论证过的，目前被认为是科学的。
一句话概括：本文注重最佳实践而非理论及推导。
已完成阅读：Chapter 1, Chapter 8
注：有些部分是理论的论证，从实用角度出发，没有必要阅读，只需要得知结论就行。
简单地讲，习得（Acquisition）就是儿童掌握母语的过程，学习（Learning） 学习就是我们课堂学习二语的过程。习得的是能力，学习的是知识。知识在反复运用后可以转换成能力。
Preface
前言部分
Error correction and explicit teaching of rules are not relevant to language acquisition, but caretakers and native speakers can modify their utterances addressed to acquirers to help them understand, and these modifications are thought to help the acquisition process.
我们的输出系统依赖于习得的语言，语言理论（语法）只是辅助手段。
Acquisition
Chapter 1 Individual Variation in the Use of the Monitor
控制输出（Monitor Use）
是指通过使用语言理论编排、组织句子后再输出。
控制输出的使用有三个条件：
- 有足够的时间；
- 专注于表达形式或者正确性；
- 使用者知道语法
但是，三种条件都符合的情况很少，所以很难成功地把有意识学习应用在语言学习过程中
The optimal user is the performer who uses learning as a real supplement to acquisition, monitoring when it is appropriate and when it does not get in the way of communication
对于控制输出，成功的使用者会在不影响交流的情况下，修改他们的输出，使得句子更加合理；过度地使用会影响交流。
Chapter 8 Relating Theory and Practice In Adult Second language Acquisition
The theoretical model clearly implies that the most important part of the entire program is the intake node under the "acquisition” node
理论模型指出整个学习过程中最重要的是输入
理想的输入条件：
- caretaker speech （保姆式地对话）
- i + 1 （对话内容在学习者的能力基础 i 上加一个等级）
- here and now （对话内容和当前相关，使得接受者的注意力不会被分散）
好的语言输入：
有意义；其目的在于交流沟通；
最好的互动：
natural、interesting and understood
教室对于成人的二语学习，至少在中级水平之前的学习是有益的
可能有用的输入情境：
there may be useful sources of intake
- the foreign student peer group(交换生有益于二语学习，他们之间的对话符合以上最佳互动特性)
- Language Learning Buttons
- Natural Approach(Students' errors are completely ignored during this activity, unless there is some communication failure.)
- extensive reading
- total physical response
intake is fundamental to acquisition.
This does not mean that speaking is not of practical importance, and it may be the case that speaking may indirectly promote language acquisition.
输入是基本，输出只是为了更好地输入
affective filter 过滤器
如果内容本身没有吸引力，或者接受者没有兴趣的话，在内容被处理之前就被过滤掉了；所以态度和兴趣很重要。
在产出之前必须先理解内容
comprehension precedes production
children acquiring second languages typically exhibit a "silent period" during which acquired competence is built up via active listening, via intake
学习语言会有“寂静期”。
The use of routines and patterns may be of immense practical value. Performers in a second language situation may need to say things very early on, before their acquired competence is "ready" to produce sentences using the acquired system.
在二语学习前期，句型句式很重要
Theoretically, routines and patterns do not contribute much to language acquisition, but practically, they may help quite a bit.
理论上讲，句型句式对于领悟语言没有啥帮助。。但是在实际上，有些帮助（在语言学习的前期）
领悟语言的第二个节点是流利地表达（Fluency）。
输出的方式有三种：
- 通过领悟系统输出（输出要慢与领悟，儿童输入之前会有一段“沉寂期”）
- 句型句式
- 通过母语转换（用到 Monitor 系统）
后两种对于输出不利
在流利表达的方面，主要目标是获得习得能力（Acquisition）。
句型句式只在前期的输出是才重要，如果允许你有一段时间的“沉寂期”，那么这个部分就不那么重要了。
Learning
The "program tree" contains two lower nodes under the "learning" node, one for rules that may be used by the optimal user for editing, and one for more difficult rules that some students may enjoy learning about.
掌握一门语言没有必要学习语法，语法先行的方法会限制授课的内容
语言学家也坦诚：他们只归纳出了一部分语法，语言老师教授的更少
结合上图，这个节点下面属于左边的语法可以学一学，右边的就算了
- the rules of thumb
- structure of language (可选，要想深入文学鉴赏方面可以学学)
The use of rules of thumb can increase accuracy in monitored performance to some extent. They will probably not make a great deal of difference in terms of communicative effectiveness, as these late-acquired items tend to be fairly redundant, but they will give the performer's writing and prepared speech a more educated appearance.
学习语法对于语言的领悟和交流没啥重要的影响，但是对于写作有帮助，所以弄清楚自己要提升的能力，再使用合理的方法训练，才会事半功倍。
There are several ways in which a classroom can promote language acquisition. Intake is available via meaningful and communicative activities supplied by the teacher; this is the most direct way the classroom can promote language acquisition. As we have seen, there are other ways in which the classroom can encourage acquisition: in second language situations, it can aid in the development of the foreign student peer group, which is quite possibly an important intermediate source of intake.
满足一定条件的课堂能够促进对于语言的掌握有帮助：
- 老师提供有意义、丰富的交流活动
- 有交换生的团体
某些通过自学外加外语学习环境在掌握二语上取得了很好效果的例子不能证明，自我学习是关键。反之，很多在学校干得漂亮的学生，在口语上很差劲。
所以，重要的还是合适的输入
语言的掌握是分部分的，某些部分比另一些要更早被掌握。
还有另外一本相关的二语学习理论：
《Principle and Practice in Second Language Acquisition》
有兴趣可以看看，注重实践价值，毕竟我们不是理论研究者，不要因为讲得很有道理而走火入魔了。
