Formal written sentences should have consistency in verb tense, pronoun agreement, clear pronoun reference, appropriate adjectives and adverbs, and agreement of subject and verb. Punctuation marks clarify the message in the written sentence. An appropriate word suits the purpose, audience, and situation. A word is a representation. A good word is as specific as possible.
Words can be concrete or abstract.
Words can have connotative as well as denotative value. Words can have symbolic meaning. Words can act as allusions. Words can act as dialect markers and language users have different oral and written vocabularies. Context influences a word's meanings.