In the study of linguistics, hypotheses formed should be based on language facts and checked against the observed facts.

Syntax is different from morphology in that the former not only studies the morphemes, but also the combination of morphemes into words and words into sentences.

Phonetics

Social changes can often bring about language changes.

Modern linguistics is mostly prescriptive, but sometimes descriptive.

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

Semantics

A scientific study of language is based on what the linguist thinks.

Both semantics and pragmatics study meanings.

Phonology