精选优质文档-倾情为你奉上1.What is mother tongue/native language?Generally, mother tongue is the first language a child has learned from birth. Because of this, it is often called first language. In most case, a persons L1 and his mother tongue mean the same. But there is still different, for example, a child was born in a foreign country.2. what is SLA?Second language acquisition refers both to the study of individuals and groups who are learning a language subsequent to learning their first o
