CONTRIBUTING: fixed some small issues

CONTRIBUTING

@@ -90,16 +90,16 @@ notice:
  *     USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
-Make sure lines never exceed 80 characters in width when using
-four-character-wide indentation steps. This helps contributors who do not have
-text wrapping in their text editors.
+Make sure lines never exceed 80 columns in width when using four-character
+indentation steps. This helps contributors who do not have access to text
+wrapping in their text editors or terminals.
 
-For usage text and help messages, please do not implement a -h option. Just
-print usage information when any erroneous option is specified. Follow the
-NetBSD style guide for usage text output format [1].
+For usage text and help messages, do not implement a -h option. Instead, print
+usage information when any erroneous option is specified. Follow the NetBSD
+style guide for the usage text’s output format [1].
 
-If committing a new source file for a utility, format the commit message like
-this:
+If committing a new source file, format the commit message following these
+guidelines:
 
 $ git commit -m 'tool(1): added feature x'
 
@@ -114,7 +114,7 @@ $ git commit -m 'tool.1: added author details'
 
 If modifying some other file or directory:
 
-$ git commit -m 'README: clarification'
+$ git commit -m 'README: clarified'
 $ git commit -m 'tests/posix: fixed bug #47'
 
 For multiple of these:
@@ -122,9 +122,11 @@ For multiple of these:
 $ git commit -m 'Makefile, tool(1): added tool(1)'
 $ git commit -m 'tool(1): added tool(1); \
 	library(3), library.3: added library(3)'
+$ git commit -m 'tool(1): fixed #42 & added feature x'
 
+Commit messages should be written in the past tense.
 
-[1] http://cvsweb.netbsd.org/bsdweb.cgi/~checkout~/src/share/misc/style
+[1] <http://cvsweb.netbsd.org/bsdweb.cgi/~checkout~/src/share/misc/style>
 
 --
 This work © 2023–2024 by Emma Tebibyte is licensed under CC BY-SA 4.0. To view a