Imagery Imagery is when a writer is showing or describing a picture. For example, the mountains were alined perfectly so the sun goes right through them.
Metaphor A metaphor is a figure of speech in which a term or phrase is applied to something to which it is not literally. The car looked like it was traveling at the speed of light.
Alliteration the occurrence of the same letter or sound at the beginning of closely connected words. An example is Peter Piper Picked a Peck of Pickled Peppers
Idiom An idiom is a group of words established by usage as having a meaning not deducible from those of the individual words. For example, it's rain cats and dogs.