diff --git a/xml/System.Text.RegularExpressions/GroupCollection.xml b/xml/System.Text.RegularExpressions/GroupCollection.xml
index 73888ee0688..52e9b6d3385 100644
--- a/xml/System.Text.RegularExpressions/GroupCollection.xml
+++ b/xml/System.Text.RegularExpressions/GroupCollection.xml
@@ -103,9 +103,9 @@
         <Parameter Name="key" Type="System.String" Index="0" FrameworkAlternate="netcore-3.0" />
       </Parameters>
       <Docs>
-        <param name="key">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="key">A string with the name of the captured group to locate.</param>
+        <summary>Determines whether the group collection contains a captured group identified by the specified name.</summary>
+        <returns><see langword="true"/> if the group collection contains a captured group identified by <paramref name="key" />; <see langword="false" /> otherwise.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -174,14 +174,12 @@
   
  ]]></format>
         </remarks>
-        <exception cref="T:System.ArgumentNullException">
-          <paramref name="array" /> is <see langword="null" />.</exception>
-        <exception cref="T:System.IndexOutOfRangeException">
-          <paramref name="arrayIndex" /> is outside the bounds of <paramref name="array" />.  
-  
- -or-  
-  
- <paramref name="arrayIndex" /> plus <see cref="P:System.Text.RegularExpressions.GroupCollection.Count" /> is outside the bounds of <paramref name="array" />.</exception>
+        <exception cref="T:System.ArgumentNullException"><paramref name="array" /> is <see langword="null" />.</exception>
+        <exception cref="T:System.IndexOutOfRangeException"><paramref name="arrayIndex" /> is outside the bounds of <paramref name="array" />.
+
+-or-
+
+<paramref name="arrayIndex" /> plus <see cref="P:System.Text.RegularExpressions.GroupCollection.Count" /> is outside the bounds of <paramref name="array" />.</exception>
       </Docs>
     </Member>
     <Member MemberName="CopyTo">
@@ -212,10 +210,17 @@
         <Parameter Name="arrayIndex" Type="System.Int32" Index="1" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="array">To be added.</param>
-        <param name="arrayIndex">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="array">The one-dimensional array that is the destination of the elements copied from the group collection. The array must have zero-based indexing.</param>
+        <param name="arrayIndex">The zero-based index in <paramref name="array" /> at which copying begins.</param>
+        <summary>Copies the elements of the group collection to a <see cref="T:System.Text.RegularExpressions.Group[]" /> array, starting at a particular array index.</summary>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.ArgumentNullException"><paramref name="array" /> is null.</exception>
+        <exception cref="T:System.ArgumentOutOfRangeException"><paramref name="arrayIndex" /> is less than zero.
+
+-or-
+
+<paramref name="arrayIndex" /> is greater than the length of <paramref name="array" />.</exception>
+        <exception cref="T:System.ArgumentException">The length of <paramref name="array" /> - <paramref name="arrayIndex" /> is less than the group collection count.</exception>
       </Docs>
     </Member>
     <Member MemberName="Count">
@@ -383,8 +388,7 @@
       </ReturnValue>
       <Docs>
         <summary>Gets a value that indicates whether access to the <see cref="T:System.Text.RegularExpressions.GroupCollection" /> is synchronized (thread-safe).</summary>
-        <value>
-          <see langword="false" /> in all cases.</value>
+        <value><see langword="false" /> in all cases.</value>
         <remarks>
           <format type="text/markdown"><![CDATA[  
   
@@ -581,8 +585,8 @@
         <ReturnType>System.Collections.Generic.IEnumerable&lt;System.String&gt;</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
+        <summary>Gets a string enumeration that contains the name keys of the group collection.</summary>
+        <value>The name keys of the group collection.</value>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -667,9 +671,10 @@
         <Parameter Name="item" Type="System.Text.RegularExpressions.Group" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="item">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="item">The group to add to the collection.</param>
+        <summary>Adds a <see cref="T:System.Text.RegularExpressions.Group" /> to the collection. Calling this method always throws <see cref="T:System.NotSupportedException" />.</summary>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.NotSupportedException">This method is not supported. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.Generic.ICollection&lt;System.Text.RegularExpressions.Group&gt;.Clear">
@@ -699,8 +704,9 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
+        <summary>Clears the collection. Calling this method always throws <see cref="T:System.NotSupportedException" />.</summary>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.NotSupportedException">This method is not supported. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.Generic.ICollection&lt;System.Text.RegularExpressions.Group&gt;.Contains">
@@ -732,10 +738,18 @@
         <Parameter Name="item" Type="System.Text.RegularExpressions.Group" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="item">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <param name="item">The group to locate in the group collection.</param>
+        <summary>Determines whether the group collection contains a specific group item.</summary>
+        <returns><see langword="true" /> if the group item is found in the group collection; <see langword="false" /> otherwise.</returns>
+        <remarks>  
+          <format type="text/markdown"><![CDATA[  
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Text.RegularExpressions.GroupCollection> instance is cast to an <xref:System.Collections.Generic.ICollection%601> interface. 
+
+         ]]></format>
+         </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.Generic.ICollection&lt;System.Text.RegularExpressions.Group&gt;.Remove">
@@ -767,10 +781,11 @@
         <Parameter Name="item" Type="System.Text.RegularExpressions.Group" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="item">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="item">The group to remove.</param>
+        <summary>Removes a <see cref="T:System.Text.RegularExpressions.Group" /> from the collection. Calling this method always throws <see cref="T:System.NotSupportedException" />.</summary>
+        <returns>This method is not supported. No value is returned.</returns>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.NotSupportedException">This method is not supported. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.Generic.IEnumerable&lt;System.Collections.Generic.KeyValuePair&lt;System.String,System.Text.RegularExpressions.Group&gt;&gt;.GetEnumerator">
@@ -798,9 +813,20 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <summary>Provides an enumerator that iterates through the group collection.</summary>
+        <returns>An enumerator that contains all names and objects in the <see cref="T:System.Text.RegularExpressions.Group" /> collection.</returns>
+        <remarks>
+          <format type="text/markdown">
+            <![CDATA[
+
+## Remarks
+
+
+Instead of calling this method to retrieve an enumerator that lets you iterate through the <xref:System.Text.RegularExpressions.Group> objects in the collection, you should use the group iteration construct (such as `foreach` in C# and `For Each`…`Next` in Visual Basic) that is provided by your programming language.
+
+          ]]>
+          </format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.Generic.IEnumerable&lt;System.Text.RegularExpressions.Group&gt;.GetEnumerator">
@@ -830,9 +856,19 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <summary>Provides an enumerator that iterates through the group collection.</summary>
+        <returns>An enumerator that contains all <see cref="T:System.Text.RegularExpressions.Group" /> objects in the group collection.</returns>
+        <remarks>
+          <format type="text/markdown">
+            <![CDATA[
+
+## Remarks
+
+Instead of calling this method to retrieve an enumerator that lets you iterate through the <xref:System.Text.RegularExpressions.Group> objects in the collection, you should use the group iteration construct (such as `foreach` in C# and `For Each`…`Next` in Visual Basic) that is provided by your programming language.
+
+          ]]>
+          </format>
+        </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.Generic.IList&lt;System.Text.RegularExpressions.Group&gt;.IndexOf">
@@ -864,10 +900,18 @@
         <Parameter Name="item" Type="System.Text.RegularExpressions.Group" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="item">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <param name="item">The group to locate in the group collection.</param>
+        <summary>Determines the index of a specific group in the group collection.</summary>
+        <returns>The index of the <paramref. name="item" /> if found; otherwise, -1.</returns>
+        <remarks>  
+          <format type="text/markdown"><![CDATA[  
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Text.RegularExpressions.GroupCollection> instance is cast to an <xref:System.Collections.Generic.IList%601> interface.
+
+         ]]></format>
+         </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.Generic.IList&lt;System.Text.RegularExpressions.Group&gt;.Insert">
@@ -900,10 +944,11 @@
         <Parameter Name="item" Type="System.Text.RegularExpressions.Group" Index="1" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="index">To be added.</param>
-        <param name="item">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="index">The position at which to insert the group.</param>
+        <param name="item">The group to insert.</param>
+        <summary>Inserts a <see cref="T:System.Text.RegularExpressions.Group" /> into the collection. Calling this method always throws <see cref="T:System.NotSupportedException" />.</summary>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.NotSupportedException">This method is not supported. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.Generic.IList&lt;System.Text.RegularExpressions.Group&gt;.Item">
@@ -936,10 +981,19 @@
         <Parameter Name="index" Type="System.Int32" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="index">To be added.</param>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <param name="index">The zero-based index of the group in the group collection.</param>
+        <summary>Gets the group at the specified position in the collection.</summary>
+        <value>The group in the desired position.</value>
+        <remarks>  
+          <format type="text/markdown"><![CDATA[  
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Text.RegularExpressions.GroupCollection> instance is cast to an <xref:System.Collections.Generic.IList%601> interface.
+
+         ]]></format>
+         </remarks>
+        <exception cref="T:System.NotSupportedException">Cannot set an item. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.Generic.IList&lt;System.Text.RegularExpressions.Group&gt;.RemoveAt">
@@ -971,9 +1025,10 @@
         <Parameter Name="index" Type="System.Int32" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="index">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="index">The zero-based index of the group to remove.</param>
+        <summary>Removes the <see cref="T:System.Text.RegularExpressions.Group" /> from the collection at the specified index. Calling this method always throws <see cref="T:System.NotSupportedException" />.</summary>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.NotSupportedException">This method is not supported. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.ICollection.CopyTo">
@@ -1111,10 +1166,10 @@
         <Parameter Name="value" Type="System.Object" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="value">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="value">The object to add to the group collection.</param>
+        <summary>Adds an object to the group collection. Calling this method always throws <see cref="T:System.NotSupportedException" />.</summary>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.NotSupportedException">This method is not supported. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.Clear">
@@ -1144,8 +1199,9 @@
       </ReturnValue>
       <Parameters />
       <Docs>
-        <summary>To be added.</summary>
+        <summary>Clears the collection. Calling this method always throws <see cref="T:System.NotSupportedException" />.</summary>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.NotSupportedException">This method is not supported. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.Contains">
@@ -1177,10 +1233,18 @@
         <Parameter Name="value" Type="System.Object" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="value">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <param name="value">The group to locate in the group collection.</param>
+        <summary>Determines whether the group collection contains a specific group item.</summary>
+        <returns><see langword="true" /> if the group item is found in the group collection; <see langword="false" /> otherwise.</returns>
+         <remarks>
+           <format type="text/markdown"><![CDATA[  
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Text.RegularExpressions.GroupCollection> instance is cast to an <xref:System.Collections.IList> interface. 
+
+           ]]></format>
+         </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.IndexOf">
@@ -1212,10 +1276,18 @@
         <Parameter Name="value" Type="System.Object" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="value">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
-        <remarks>To be added.</remarks>
+        <param name="value">The group to locate in the group collection.</param>
+        <summary>Determines the index of a specific group in the group collection.</summary>
+        <returns>The index of the <paramref. name="item" /> if found; otherwise, -1.</returns>
+         <remarks>
+           <format type="text/markdown"><![CDATA[  
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Text.RegularExpressions.GroupCollection> instance is cast to an <xref:System.Collections.IList> interface. 
+
+           ]]></format>
+         </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.Insert">
@@ -1248,10 +1320,11 @@
         <Parameter Name="value" Type="System.Object" Index="1" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="index">To be added.</param>
-        <param name="value">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="index">The position at which to insert the group.</param>
+        <param name="value">The group to insert.</param>
+        <summary>Inserts a <see cref="T:System.Text.RegularExpressions.Group" /> into the collection. Calling this method always throws <see cref="T:System.NotSupportedException" />.</summary>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.NotSupportedException">This method is not supported. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.IsFixedSize">
@@ -1281,9 +1354,17 @@
         <ReturnType>System.Boolean</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <summary>Gets a value indicating whether the group collection has a fixed size.</summary>
+        <value><see langword="true" /> always.</value>
+         <remarks>
+           <format type="text/markdown"><![CDATA[  
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Text.RegularExpressions.GroupCollection> instance is cast to an <xref:System.Collections.IList> interface. 
+
+           ]]></format>
+         </remarks>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.Item">
@@ -1316,10 +1397,19 @@
         <Parameter Name="index" Type="System.Int32" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="index">To be added.</param>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <param name="index">The zero-index position of the group in the group collection.</param>
+        <summary>Gets the group in the desired position.</summary>
+        <value>The group in the desired position.</value>
+         <remarks>
+           <format type="text/markdown"><![CDATA[  
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Text.RegularExpressions.GroupCollection> instance is cast to an <xref:System.Collections.IList> interface. 
+
+           ]]></format>
+         </remarks>
+        <exception cref="T:System.NotSupportedException">Cannot set an item. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.Remove">
@@ -1351,9 +1441,11 @@
         <Parameter Name="value" Type="System.Object" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="value">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="value">The group to remove.</param>
+        <summary>Removes a <see cref="T:System.Text.RegularExpressions.Group" /> from the collection. Calling this method always throws <see cref="T:System.NotSupportedException" />.</summary>
+        <returns>This method is not supported. No value is returned.</returns>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.NotSupportedException">This method is not supported. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="System.Collections.IList.RemoveAt">
@@ -1385,9 +1477,10 @@
         <Parameter Name="index" Type="System.Int32" Index="0" FrameworkAlternate="netcore-2.0;netcore-2.1;netcore-2.2;netcore-3.0;netstandard-2.1" />
       </Parameters>
       <Docs>
-        <param name="index">To be added.</param>
-        <summary>To be added.</summary>
+        <param name="index">The zero-based index of the group to remove.</param>
+        <summary>Removes the <see cref="T:System.Text.RegularExpressions.Group" /> from the collection at the specified index. Calling this method always throws <see cref="T:System.NotSupportedException" />.</summary>
         <remarks>To be added.</remarks>
+        <exception cref="T:System.NotSupportedException">This method is not supported. This is a read-only collection.</exception>
       </Docs>
     </Member>
     <Member MemberName="TryGetValue">
@@ -1416,10 +1509,10 @@
         <Parameter Name="value" Type="System.Text.RegularExpressions.Group" RefType="out" Index="1" FrameworkAlternate="netcore-3.0" />
       </Parameters>
       <Docs>
-        <param name="key">To be added.</param>
-        <param name="value">To be added.</param>
-        <summary>To be added.</summary>
-        <returns>To be added.</returns>
+        <param name="key">A string with the group name key to look for.</param>
+        <param name="value">When the method returns, the group whose name is <paramref name="key" />, if it is found; otherwise, <see langword="null" /> if not found.</param>
+        <summary>Attempts to retrieve a group identified by the provided name key, if it exists in the group collection.</summary>
+        <returns><see langword="true" /> if a group identified by the provided name key exists; <see langword="false" /> otherwise.</returns>
         <remarks>To be added.</remarks>
       </Docs>
     </Member>
@@ -1448,10 +1541,18 @@
         <ReturnType>System.Collections.Generic.IEnumerable&lt;System.Text.RegularExpressions.Group&gt;</ReturnType>
       </ReturnValue>
       <Docs>
-        <summary>To be added.</summary>
-        <value>To be added.</value>
-        <remarks>To be added.</remarks>
+        <summary>Gets a group enumeration with all the groups in the group collection.</summary>
+        <value>A group enumeration.</value>
+        <remarks>  
+          <format type="text/markdown"><![CDATA[  
+
+## Remarks
+
+This member is an explicit interface member implementation. It can be used only when the <xref:System.Text.RegularExpressions.GroupCollection> instance is cast to an <xref:System.Collections.Generic.IEnumerable%601> interface. 
+
+         ]]></format>
+         </remarks>
       </Docs>
     </Member>
   </Members>
-</Type>
\ No newline at end of file
+</Type>