I find it very hard sometimes to describe a scenery, especially when the features are very bland, like you describe a city where all of the buildings are tall and look about the same or a plain with green grass with a sprinkle of green leafy trees. What are some ways of extending a descriptive paragraph?
When describing the scenery, your goal isn't only to convey dry information (there are houses, there are trees, etc.). Your goal is to evoke some emotion, some feeling. Your key to extending the description of the scenery is therefore in what feeling you wish to evoke.
For example, I look at a desert - miles and miles of yellow dunes stretching before me. All same-y, you could say. But how do I feel? Am I in awe of the beauty, the colours, the magnificence and sheer size of God's creation? In such a case, description would focus on the colours, the play of light and shade, the changing patterns of the sand.
Am I apprehensive, because I need to cross this desert, and there's the risk of getting lost, and while I should have enough water, I can afford no accidents, and who knows what's hiding in there? In such a case, the description would focus on the heat, and how I can see nothing but sand stretching to the horizon, and the sun beats on my face (a violent verb).
If you describe a city, are the buildings tall and oppressive, the streets narrow, the air stifling, do you feel small, do you feel you do not belong in this city?
Or are the tall buildings straining to touch the sky, a proud testimony to man's ingenuity, and you're excited to walk among them?
If you're describing "home", do you wish to evoke a sense of comfort and warmth, or a sense of boring familiarity one's eager to leave on an adventure?
Start from what you wish to evoke, and then find in the scenery the elements that support that feeling. You can use sight, sounds, smell, temperature, your character can be reminded of something, but it all should paint one image, one emotion.
+1 Galastel. I would add to her answer memories. If my MC has never seen it before, how does what she see connect in her memory?
What has she been told about this place? By whom?
If she has been here before, what was the occasion? How has it changed since then? You give the reader a sense of time this way. It's been five years, and these houses out here occupy what was empty farmland. That skyscraper is new. This street has been widened. It's dirtier than she recalled, the wind liberating scraps of paper from overflowing trash cans. Or was she just inured to the filth back then? Perhaps she had become spoiled, living in the Capitol.
She can remember these things, and filter the details through her own life experience. Your description doesn't have to be just raw description of the setting. Consider that (just raw description) as similar to a wall of dialogue. The wall of dialogue can be under-imagined, it leaves out the setting, the people moving, thinking, remembering and feeling, their physical actions.
Just description can be similar. You aren't painting a picture, you have a mind looking at a picture. Just the description can be under-imagined because you aren't imagining what these visions are doing to your character. Like talking, Viewing can be presented as an active experience influencing the mood, feelings, memories and plans of the viewer.
So anchor your writing in description of the setting, but in a character-influencing way. Consider her personality: What is she looking for in this landscape?
If she has been a soldier all her life, she may be naturally looking for threats, for ambush points, for people. For water, food or supplies. I would detail what she sees through the lens of somebody always assessing a landscape in anticipation of battle, places of safety, lairs for ambush, lines of sight, defensible positions and gravitating to explore those first, even if she is in no immediate danger -- That's just how her mind works; threat assessment first.
If you have multiple characters viewing this spectacle, they are all affected by it, and each have their own personality and memories. They can have a conversation about that -- but again remember to anchor it in descriptions of the setting, so their conversation is driven by observations about the setting and the memories and emotions it triggers in them.
When describing scenery is coming out a little flat, I try to add a few specific items to be descriptive about. I usually pick three or seven because they are magic numbers (depending on how much detail I think the scene needs added to it) and I try to be specific.
For example, in my city, with tall buildings that all look the same, I may describe a storefront window, or a wall with graffiti on it (maybe layers of graffiti), or a broken fire hydrant leaking water into the street, or the potholes, or a homeless panhandler, or some shiny mural that there city recently had an artist put up.
These details will start to give your reader something to visualize as you talk about your scene, and you can use them as landmarks at other points in the story.
Not only will this give your scene some uniqueness, but it will set a mood and tone for your story. The homeless guy evokes different emotions than a beautiful mural, and graffiti something else. Do you want your city to be run-down and drab, or lovely and colorful?
The nice thing about these little specifics is they can be used to add symbols with extra layers of meaning. Or foreshadowing. Or any literary device you can think of. For instance, won't it be poetic, when later in the story a fire breaks out and the fire department shows up, but the hydrant is broken? The storefront you described burns while they find an alternate, but they manage to stop the fire just before it reaches the mural, which happens to depict the aftermath of a major fire from one-hundred and eighty-seven years ago.
When scenery reflects the character's state of mind, it's a blurring of the narrative voice from an "impartial" narrator, to a biased "character-filtered" representation of the world.
Jane Austin's Free Indirect Speech is third-person omniscient, but changes the narrator into the unspoken opinions of various characters. Extremely biased and contradictory statements are made matter-of-factly by the narrative voice.
H P Lovecraft piles on character-biased descriptions of flora and fauna, "unnatural" colors, sinister locals, etc. Things that are otherwise mundane or unexplained take on thematic significance through their sinister descriptions.
Scenery is never just scenery. It's an external representation of the character's internal landscape.