The word ‘diction’ has its origin in the Latin word ‘dicere’ i.e. to say so, ‘Diction’ in a novel refers to the selection of words that form the language of a novel.
‘Syntax’ refers to the structure of sentences or simply stated, the order or arrangement of words in sentences that form the language used in a novel. A correct syntax leads to greater comprehension as the sentences are grammatically error-free and make sense.
Style is language as a whole, complete, considering all aspects. It includes diction, syntax, literary devices all working together to bring the novel to life for the reader.
Because novels are to be written under some time/historical statements and the characters are to be seeming part of the history itself meaning reality to the story told.
