Decide which structure is used in the following sentences. first, i wash my face. next, i brush my teeth. then, i put on my pajamas. at last, i lay down. finally, i fall asleep.

C) Chronological order.

Explanation: Chronological order is a method of organization that consists in the arrangement of things following one after another in time (in the order they happen). In the given paragraph we can see a list of steps that the speaker does before going to sleep. As we can see, he/she describes the things she/he does in the order that she/he does them. So the used structure is chronological.

- "the basic difference between keywords and subjects is that subjects (or "subject headings") have been predetermined, while keywords have not. a keyword is an easy place to start because you can use any word that seems to fit your search; this is called "natural language" searching."