Picture of Fritz Arnold, by his daughter Ruby Arnold:

Present Tense is the language of description.
Remember how we define a scene:
A SCENE is a continuous unit of time and space. If we jump ahead or back in time, we'll be in another scene.  If we change locations, we're in another scene.
The SLUGLINES and also "Supers" will tell us that we're in a new scene, and where we are, and what time period we're traveling to enter. That also means we do not have to write "The End" when a scene ends.
Writing in all our formats, means our action descriptions are always in present tense. 
Here's how we'd travel to another pandemic time.

EXT. BATTLEFIELD - DAY
Smoke is billowing, Guns are SHOOTING non-stop.  But louder than any other sound is unrelenting COUGHING as we move towards a small first-aid Canvas tent.

SUPER
1917

Notice how, even though we 'were' in 1917 - on screen we're in the present tense of what the world is like for Soldiers & Nurses & doctors in that year. It is always another version of "now" in film, and that's one of the many reasons it's so powerful and popular,

Of course, in dialogue, Characters may use any tense they wish!

 Locations  tickle the imagination, attract the eyes, open the lens of our vision... 

As an exercise, pick any of these places  and write a description of them. Don't use any CAMERA SHOTS. 

 
Right now, have fun - with pictures for inspiration.

 Action Description in film does what Action Description in books can do - it sets the world of the writer's imagination on the page in such a way that a script reader cam imagine the film during the read.

Check out the PDF of the opening of Charles Dickens' 'Bleak House' - we can imagine the shots and sounds as we read the text. 

Notice how Charles Dickens uses language to establish images and movement...that's a good clue to help discover your own voice for action

...it's how you tell your stories that matters - in your own voice. 

Write Like the Dickens



Production Notes: 

I always suggest that writers read aloud the pages generated in each day's writing. Read dialogue and all descriptions aloud . You'll hear the difference right away. The reader may see the difference when she’s reading the script of a writer who knows about the necessity of ongoing revisions.

By pre-production time, you have a good sense of where your script is going.  As a regular part of the work pattern in script-writing, it's, of course, vital to keep the forward motion; to arrive at the point where you hope to bring the script. In addition, a regular part of the script-writing process is, as well,  to be doing tidy-up work with the previous pages.

One of the first things that happens in the initial production process is a continuing checking of the script.  Many times, in all production worlds, we'll need to suddenly change pages & shift things around depending on the production schedule. Get used to this process in advance...it will give us all a much longer writing career.

When we're flexible, but also not afraid to neutrally defend our position, all goes well.  However, when there's a point-of-view that always defends, when there are pages that never seem to change no matter what the notes, the writer is in a precarious position. All things change in some way, like life, as we approach actual production.

Approaches:

When a new writer approaches the production process, there are a few approaches that are a given: The script pages you submit, as a draft to a production house, must actually be script pages and not a disguised treatment; the characters need to have names when required, and Extras are named in such a way that it remains easy to see and hear the action without a need to look back to a previous page to see if we know who the hell the attackers are, or see the representative of the Cops, or Fire-fighters, or Elves, Aliens, or Paramedics...

When you look at Extras look for one or two, at least, that you can name or describe in such a way that we'll 'see' them in mind at once ..And, when we've received all our Rough Draft, or First Draft notes - the studio/Story Consultant will expect to see a reflection of their notes appearing in the next submission.

This is a form where flexibility is a vital key to being able to enter the business/art/craft, and to remain active in it. There are a few red-flags for show-runners, and one of them is to notice when pages seldom get a touch-up, lines aren't being adjusted; where many names are abstract, (Cop #1, Cop # 76, Cop # 22 & so on.  As well, settings are rarely described.  

We adjust our formatting approaches depending on the Network, Production House, and the Story-Consultant who will work with us.  If you do a script for one Network, you may follow the approaches of Warner's Script formatting. However, the next studio may have their own approach. The writer adjusts to that specific. 

 If we talk with our peers who keep the Indy lights going, each will have an even more vital reason to have formatting reflect production practices. If the formatting practices of the house aren't followed, and do NOT get reflected, it's as big a deal as missing a deadline. And getting the script in at the specified time needed, is a very big expectation on the part of producers.

The closer we get to actual production, the more impact on the approaching shoot & what we need to do in response to Production notes.

Here's a few quick examples:  We want to make sure that our KEY PROPS get ALL-CAPS. If it's a GATLING-GUN being assembled in a kitchen, we make sure someone remembers to have the weapon on set.  If it's fired, it needs to be able to be fired and so on. The ALL-CAPS make the production-attention go to the description on the page. Standard and expected props do not need such a treatment.  If someone is at a kitchen table and has in front of them cutlery, plates, a tablecloth...you don't need to ALL-CAP those props. If you have a PET PIG wandering around the GATLING GUN, there'd be ALL-CAPS where I just indicated.

If we have Extras arrive on set, we ALL-CAP the EXTRAS the first time they appear in a new scene.  If we have a group, or a crowd, or a riot, we take the time to describe the setting, and give images of the kind of crowd, the sort of people who will be present in the scene. We ALL-CAP a character the first time they appear in a script, and give a quick description which conveys what we know about them & delivers a sense of the scene to the imagination.