General linguistics, which relates itself to the research of other areas, studies the basic concepts, theories, descriptions, models and methods applicable in any linguistic study.

D（）is one of the design features of human language which refers to the phenomenon that language consists of two levels: a lower level of meaningless individual sounds and a higher level of meaningful units.

Morphology

Language

The discipline that studies the rules governing the formation of words into permissible sentences in languages is called s（）

The study of the ways in which morphemes can be combined to form words is called morphology.

Morphology studies how words can be formed to produce meaningful sentences.

Phonology

General linguistics is generally the study of language as a whole.

Phonetics