Do people use the same language in all settings and contexts? Your first answer might be "sure," but try this test. For a couple of hours, or even a day, pay attention to how you speak, and how others speak: the words you say, how you say them, the pacing and timing used in each context. For example, at home in the morning, in the coffee shop before work or class, during a break at work with peers or a break between classes with classmates all count as contexts. Observe how and what language is used in each context and to what degree they are the same or different.