Imagine you are standing outside of your house, facing the front door. Describe what you see as objectively as possible, in as much detail as you can.
Next imagine that in this house lives a violent serial killer who has taken a loved one hostage (try not to scare yourself though!). Now, describe what you see again, but this time try to convey the sense of dread you would feel if this was actually the case. Don’t describe thoughts, only describe what you can physically see.
Finally, imagine that it is your birthday and all of your friends and family are gathered within your house, waiting for you to arrive to help you celebrate. Describe the scene again. What has changed? How were the descriptions different? Note the words that you used in each section, and how they convey different atmospheres.