Stylistic Devices of Omission
Figures of omission are based on incompleteness of sentence structure: AB_DEF
Ellipsis consists in omission of some parts of the sentence that are easily understood from the context or situation. In colloquial style this omission simply makes the speech more compact:
E.g. Where is he? – In the garden.
In literary descriptions it may give the construction an additional expressive or emotional colouring.
E.g. The sea is but another sky,
The sky a sea as well… (Longfellow)