a simile: a figure of speech involving the comparison of one thing with another thing of a different kind, used to make a description more emphatic or vivid (e.g., as brave as a lion, crazy like a fox).
or in other words the using of like or as in order to bring a comparison to two separate entities.
Explanation:imperative is a command to do something if you want to get a certain result and categorical means it's unconditional hence if you don't shut the door you will not hear.
