单项选择题
As modern linguistics aims to describe and analyze the language people actually use, and not to lay down rules for "correct" linguistic behavior,it is said to be （）.
A.prescriptive B.sociolinguistic C.descriptive D.psycholinguistic
名词解释 Duality
问答题 Describe the process of language perception，comprehension and production.
问答题 Why do we say tree diagrams are more advantageous and informative than linear structure in analyzing the constituent relationship among linguistic elements Support your statement with examples?
