He might sleep in the belief that the silence of the grave would quench forever the transient existence of the hideous corpse wh
ich he had looked upon as the cradle of life. He sleeps; but he is awakened; he opens his eyes; behold the horrid thing stands at his bedside, opening his curtains, and looking on him with yellow, watery, but speculative eyes. Which words best describe Mary Shelley’s style of writing in her introduction to Frankenstein?
To be imaginative means to be creative - with words, in this case.
The use of metaphorical comparisons in the excerpt is an example of an imaginative technique. Phrases such as "Silence of the grave", "Cradle of life", and "Opening his curtains" are examples of these metaphors.
The dark tone comes when the character begins to awaken, as they slowly discover their horrid appearance.