_____ refers to the phenomenon that those who do not share a first language communicate with each other in a language that they know.
A、national language
B、lingua franca
C、official language
D、world language
_____ refers to the phenomenon that those who do not share a - Lecture 7 Sociolinguistics - 应用语言学入门 - U校园 | 大学网课搜题引擎