docs: more fluent English

Co-authored-by: adeshpande <[email protected]>

Author: HairlessVillager

docs/source/tutorials/output_and_config.rst

@@ -276,7 +276,7 @@ When executing the command
 
    manim -pql scene.py SquareToCircle
 
-it specifies the scene to render.  This is not necessary now.  When a single file contains only one ``Scene`` class, it just render the only one.  When a single file contains more than one ``Scene`` class, you can leave a blank, and the manim will let you choose a ``Scene`` class.  If your file contains multiple ``Scene`` classes, and you want to render them all, you can use the ``-a`` flag.
+it specifies the scene to render.  This is not necessary now.  When a single file contains only one ``Scene`` class, it will render that class.  When a single file contains more than one ``Scene`` class, manim will let you choose a ``Scene`` class.  If your file contains multiple ``Scene`` classes, and you want to render them all, you can use the ``-a`` flag.
 
 As discussed previously, the ``-ql`` specifies low render quality (854x480 15FPS).  This does not look very good, but is very useful for rapid prototyping and testing.  The other options that specify render quality are ``-qm``, ``-qh``, ``-qp`` and ``-qk`` for medium (1280x720 30FPS), high (1920x1080 60FPS), 2k (2560x1440 60FPS) and 4k quality (3840x2160 60FPS), respectively.