[css-speech-1] Fix more typos

Author: fantasai

css-speech-1/Overview.bs

@@ -603,7 +603,7 @@ The 'pause-before' and 'pause-after' properties</h3>
 		<dd>
 			Equivalent to 0ms (no prosodic break is produced by the speech processor).
 
-		<dt><dfn>x-weak</dfn>, <dfn>weak</dfn>, <dfn>medium</dfn>, <dfn>dfn</dfn>, and <dfn>x-dfn</dfn>
+		<dt><dfn>x-weak</dfn>, <dfn>weak</dfn>, <dfn>medium</dfn>, <dfn>strong</dfn>, and <dfn>x-strong</dfn>
 
 		<dd>
 			Expresses the pause by the strength of the prosodic break in speech output.
@@ -677,7 +677,7 @@ Collapsing pauses</h3>
 	</ul>
 
 	A collapsed pause is considered adjoining to another pause
-	f any of its component pauses is adjoining to that pause.
+	if any of its component pauses is adjoining to that pause.
 
 	Note: 'pause' has been moved from between the element's contents and any 'cue'
 	to outside the 'cue'.
@@ -720,7 +720,7 @@ The 'rest-before' and 'rest-after' properties</h3>
 			Equivalent to 0ms.
 			(No prosodic break is produced by the speech processor.)
 
-		<dt><dfn>x-weak</dfn>, <dfn>weak</dfn>, <dfn>medium</dfn>, <dfn>dfn</dfn>, and <dfn>x-dfn</dfn>
+		<dt><dfn>x-weak</dfn>, <dfn>weak</dfn>, <dfn>medium</dfn>, <dfn>strong</dfn>, and <dfn>x-strong</dfn>
 		<dd>
 			Expresses the rest by the strength of the prosodic break in speech output.
 			The exact time is implementation-dependent.
@@ -840,7 +840,7 @@ The 'cue-before' and 'cue-after' properties</h3>
 Relation between audio cues and speech synthesis volume levels</h3>
 
 
-	<em>This section is non-normative>
+	<em>This section is non-normative.</em>
 
 	The volume levels of audio cues and of speech synthesis
 	within the [=aural box model=] of a selected element are related.
@@ -1312,7 +1312,7 @@ The 'voice-range' property</h3>
 
 	<pre class=propdef>
 	Name: voice-range
-	Value: <<frequnecy>> && absolute | [[x-low | low | medium | high | x-high] || [<<frequency>> | <<semitones>> | <<percentage>>]]
+	Value: <<frequency>> && absolute | [[x-low | low | medium | high | x-high] || [<<frequency>> | <<semitones>> | <<percentage>>]]
 	Initial: medium
 	Applies to: all elements
 	Inherited: yes