What are the main difficulties the adult learners face when learning a second language? How do they compare to young learners?

Do you think it is possible for adult learners completely to overcome the challenges posed by critical periods? If so, what are some ways to help them reach native proficiency in the second language? （How do factors such as motivation, immersion, or technology affect adult language acquisition?）

How do you think this research can inform TESOL teaching practices, especially for adult learners? Should teachers use different strategies when working with older language learners?

How much do you think age affects language learning ability? Has this been felt in your learning?