Updated Boolean guidance and a bug fix (#551)

* Updated Boolean guidance and a bug fix

* Update to Boolean entry

Author: julian-cable

en-US/B.xml

@@ -227,9 +227,18 @@
 					Correct. Named after George Boole, who first developed the concept.
 				</para>
 				 <para>
-					According to the <citetitle>IBM Style Guide</citetitle>, it is acceptable to use "boolean" in API programming information when it refers to a primitive return type.
+					According to the <citetitle>IBM Style Guide</citetitle>, it is acceptable to use "boolean" (lowercase) in API programming information when it refers to a primitive return type.
 				</para>
-
+				 <para>
+					To set Boolean values in YAML files, use <varname>true</varname> or <varname>false</varname>, written lowercase, rather than <varname>yes</varname> or <varname>no</varname>, because YAML&nbsp;1.2 and later versions do not support the latter syntax.  
+				</para>
+				 <para>
+					For example, the following scenario specifies that a task is run only one time:  
+				</para>
+<screen>- name: Pause 30 seconds
+  ansible.builtin.pause:
+    seconds: 30
+  <userinput>run_once: true</userinput></screen>
 			</listitem>
 
 		</varlistentry>

en-US/Grammar.xml

@@ -932,7 +932,7 @@ Split contractions and abbreviations into separate paragraphs. -->
 		<title>Contractions and Abbreviations</title>
 		 <para>
 			Do not use contractions in Red&nbsp;Hat documents.
-      For example, do not use can't, "don't", "won't", and similar examples.
+      For example, do not use "can't", "don't", "won't", and similar examples.
       Write out the words in full.
       Contractions are a mark of informal writing, and should be avoided when writing technical documentation or other more formal types of manuals.
       They can also cause problems for translation.