IT IS A LITERARY DEVICE WHERE YOU GIVE HUMAN-LIKE QUALITIES TO NON-HUMAN ELEMENTS.
EUPHEMISM
I AM LETTING YOU GO
YOU'RE FIRED
COMPARISONS BETWEEN TWO ONE THING WITH ANOTHER THING OF A DIFFERENT KIND.
COLLOQUIALISM
HI BRO! WHAT'S UP?
ALL GOODS, MATE!
Lucy was amazed to find herself under water, but still able to breathe. She had no time to dwell on the impossible; a mermaid swam up and asked for her help to defeat monsters that were attacking her home.
Expression substituted for one considered to be too harsh or blunt when referring to something unpleasant or embarrassing.
Colloquial language is the linguistic style used for casual communication. It is the most common functional style of speech, the idiom normally employed in conversation and other informal contexts.
With new-found confidence in herself, Lucy returned through the tree's portal with her prize. After facing monsters at the bottom of the ocean, she felt able to brave the darkness of the woods. After all, her cell phone's light was her greatest weapon.