How do you think raising student's metalinguistic awareness would help promoting their secend language acquisition proficiency?

Before answering the question I would like to explain the term "metalinguistics or metalinguistic awareness". This term is used for the ability to think about a language and to try the appropriate use of its vocabulary....etc.

Definitely, metalinguistic awareness is a high class tool to promote the learners abilities at a level to acquire proficiency in a fast pace. It helps the learner to learn vast vocabulary, body language, facial expressions, accent and the right time to use right words, etc. The learner feels more confident with metalinguistic awareness.