The Age Factor in Learning a Second Language
Description:
Discuss how Singleton defends the claim that adult L2 learners are initially more efficient, but in the long run the younger a learner is when when the L2 acquisition process begins, the more successful the outcome of that process will be. (This claim is proposition (4) which Singleton defends , in chapter 4 of Language Acquisition: The Age Factor, 2nd edn (Cldvedon: Multilingual Matters, 2004), available in Kindle ebook.
Show clearly how he defends it, and critically evaluate it.
You should present relevant evidence, and use academic sources.