Metaphor is the same as simile (regarded as equivalent to something but not associated with it) but without the words
like or
as:
Lexical metaphor
She is a rose. Metaphor
She is like a rose. Simile
Grammatical metaphor: Meaning construed in a different way by means of a different grammatical construction:
The brakes failed. The brake failure (transforming lexical to grammatical metaphor)
Congruent vs metaphorical expressions:
Congruent (literal) as opposed to the metaphorical realization of meaning.
This is a very wide area the best way for you first is to go to
Wikipedia click on English and search for:
Metaphor
conceptual metaphor
grammatical metaphor
Metaphor is a never-ending topic. You can only discuss certain areas after you have read the articles.l