English improvements for content guidelines

This commit simplfies many sentences and rewords many sentences to make
them sound more natural. In some places, this commit rewords sentences
to make their structure more parallel. The goal of all of these changes
is to make the content guidelines easier to understand.

Before this commit, the paragraph at the bottom of “Guidelines and
principles” said pretty much the same thing that the paragraph at the
bottom of “Limiting cognitive load” said. This commit combines those two
paragraphs to  reduce redundancy.

community/contributing/content_guidelines.rst

@@ -3,23 +3,23 @@
 Content guidelines
 ==================
 
-This document is here to help us assess what we should include in the official
-documentation. Below, you will find a couple of principles and recommendations
-to write accessible content.
+This document outlines what should be included in the official documentation.
+Below, you will find a couple of principles and recommendations for writing
+accessible content.
 
 We want to achieve two goals:
 
 1. **Empathize with our users.** We should write in a way that makes it easy for
    them to learn from the docs.
 2. **Write a complete reference manual**. Our goal here is not to teach
-   programming foundations. Instead, we should provide a reference for how
+   programming fundamentals. Instead, our goal is to provide a reference for how
    Godot's features work.
 
 Guidelines and principles
 -------------------------
 
 Below are the guidelines we should strive to follow. They are not hard rules,
-though: exceptionally, a topic will require breaking one or more of these.
+though: sometimes, a topic will require breaking one or more of them.
 Still, we should strive to achieve the two goals listed above.
 
 Writing complete and accessible documentation
@@ -36,15 +36,15 @@ should ensure that we cover everything Godot does.
     when their work gets merged and requires documentation.
 
 Do your best to keep documents **under 1000 words in length**. If a page goes
-past that threshold, consider splitting it into two parts if possible. Limiting
-page size forces us to write concisely and to break large documents so they each
-focus on a particular problem.
+past that threshold, consider splitting it into two parts. Limiting page size
+forces us to write concisely and to break up large documents so that each page
+focuses on a particular problem.
 
-Make it clear what **problem** each page or section of a page tackles and what
-the user will learn from it. Users need to know if they're reading the correct
-guide to solving problems they encounter. For example, instead of writing the
-heading "Signals", consider writing "Reacting to changes with signals". The
-second title makes it clear what the purpose of signals is.
+Each page or section of a page should clearly state what **problem** it tackles
+and what it will teach the user. Users need to know if they're reading the
+correct guide for solving the problems they're encountering. For example,
+instead of writing the heading "Signals", consider writing "Reacting to changes
+with signals". The second title makes it clear what the purpose of signals is.
 
 .. note::
 
@@ -52,9 +52,12 @@ second title makes it clear what the purpose of signals is.
     navigation cumbersome. Try to keep headings five words long or less.
 
 If the page assumes specific knowledge of other Godot features, mention it and
-link it to the corresponding documentation. For instance, a page about physics
-may use signals, in which case we could note that the page that introduces
-signals is a pre-requisite.
+link to the corresponding documentation. For instance, a page about physics
+may use signals, in which case you could note that the signals tutorial is a
+prerequisite. You may also link to other websites for prerequisites beyond the
+documentation's scope. For example, you could link to an introduction to
+programming in the getting started guide, or a website that teaches math theory
+in the math section.
 
 Limiting cognitive load
 ~~~~~~~~~~~~~~~~~~~~~~~
@@ -66,17 +69,17 @@ learn. You can do so by:
 1. Introducing only one new concept at a time whenever possible.
 2. Using simple English, as we recommend in our writing guidelines.
 3. Including one or more **concrete usage examples**. Prefer a real-world example
-   to abstract code like ``foobar``.
+   to one that uses names like ``foo``, ``bar``, or ``baz``.
 
 While many people may understand more complex language and abstract examples,
-you will lose others. Also, understandable writing and practical examples
-benefit everyone.
+you will lose others. Understandable writing and practical examples benefit
+everyone.
 
 Always make an effort to **put yourself in the user's shoes**. When we
-understand something thoroughly, it becomes evident to us. We may fail to think
+understand something thoroughly, it becomes obvious to us. We may fail to think
 about details relevant to a newcomer, but **good documentation meets users where
-they are**. We should strive to explain each feature's capabilities or intended
-uses with the most straightforward language possible.
+they are**. We should explain each feature's capabilities or intended uses with
+the most straightforward language possible.
 
 Try to remember what you first needed to know when learning about the feature or
 concept. What new terms did you need to learn? What confused you? What was the
@@ -85,13 +88,7 @@ practice explaining the feature before writing about it.
 
 .. note::
 
-    Having programming foundations is a pre-requisite to use a complex engine
-    like Godot. Talking about variables, functions, or classes is acceptable.
-    But we should favor plain language over specific terminology like
+    Programming fundamentals are a prerequisite for using a complex engine like
+    Godot. Talking about variables, functions, or classes is acceptable. But we
+    should favor plain language over specific terminology like
     "metaprogramming". If you need to use precise terms, be sure to define them.
-
-When a page assumes knowledge of another engine feature, declare it at the
-beginning and link to resources that cover what users need. You may also link to
-other websites for pre-requisites beyond the documentation's scope. For example,
-you could link to an introduction to programming in the getting started guide, or a
-website that teaches math theory in the math section.