diff --git a/src/Microsoft.Management.UI.Internal/ManagementList/ManagementList/ManagementListStateDescriptor.cs b/src/Microsoft.Management.UI.Internal/ManagementList/ManagementList/ManagementListStateDescriptor.cs
index 45db449d7..668118a5b 100644
--- a/src/Microsoft.Management.UI.Internal/ManagementList/ManagementList/ManagementListStateDescriptor.cs
+++ b/src/Microsoft.Management.UI.Internal/ManagementList/ManagementList/ManagementListStateDescriptor.cs
@@ -136,7 +136,7 @@ namespace Microsoft.Management.UI.Internal
         /// </summary>
         /// <param name="subject">Target ManagementList.</param>
         /// <param name="callback">RetryActionAfterLoaded callback method.</param>
-        /// <returns>True iff columns restorable.</returns>
+        /// <returns>True if-and-only-if columns are restorable.</returns>
         /// <exception cref="InvalidOperationException">
         /// ManagementList.AutoGenerateColumns not supported.
         /// </exception>
diff --git a/src/Microsoft.PowerShell.Commands.Management/commands/management/Service.cs b/src/Microsoft.PowerShell.Commands.Management/commands/management/Service.cs
index ec6e8062d..b46f21dc6 100644
--- a/src/Microsoft.PowerShell.Commands.Management/commands/management/Service.cs
+++ b/src/Microsoft.PowerShell.Commands.Management/commands/management/Service.cs
@@ -888,7 +888,7 @@ namespace Microsoft.PowerShell.Commands
         /// This will start the service.
         /// </summary>
         /// <param name="serviceController">Service to start.</param>
-        /// <returns>True iff the service was started.</returns>
+        /// <returns>True if-and-only-if the service was started.</returns>
         internal bool DoStartService(ServiceController serviceController)
         {
             Exception exception = null;
@@ -944,7 +944,7 @@ namespace Microsoft.PowerShell.Commands
         /// <param name="serviceController">Service to stop.</param>
         /// <param name="force">Stop dependent services.</param>
         /// <param name="waitForServiceToStop"></param>
-        /// <returns>True iff the service was stopped.</returns>
+        /// <returns>True if-and-only-if the service was stopped.</returns>
         internal List<ServiceController> DoStopService(ServiceController serviceController, bool force, bool waitForServiceToStop)
         {
             // Ignore ServiceController.CanStop.  CanStop will be set false
@@ -1094,7 +1094,7 @@ namespace Microsoft.PowerShell.Commands
         /// This will pause the service.
         /// </summary>
         /// <param name="serviceController">Service to pause.</param>
-        /// <returns>True iff the service was paused.</returns>
+        /// <returns>True if-and-only-if the service was paused.</returns>
         internal bool DoPauseService(ServiceController serviceController)
         {
             Exception exception = null;
@@ -1174,7 +1174,7 @@ namespace Microsoft.PowerShell.Commands
         /// This will resume the service.
         /// </summary>
         /// <param name="serviceController">Service to resume.</param>
-        /// <returns>True iff the service was resumed.</returns>
+        /// <returns>True if-and-only-if the service was resumed.</returns>
         internal bool DoResumeService(ServiceController serviceController)
         {
             Exception exception = null;
diff --git a/src/Microsoft.PowerShell.ConsoleHost/host/msh/ConsoleHostUserInterfacePrompt.cs b/src/Microsoft.PowerShell.ConsoleHost/host/msh/ConsoleHostUserInterfacePrompt.cs
index 7b81bb8a9..5895dcf2b 100644
--- a/src/Microsoft.PowerShell.ConsoleHost/host/msh/ConsoleHostUserInterfacePrompt.cs
+++ b/src/Microsoft.PowerShell.ConsoleHost/host/msh/ConsoleHostUserInterfacePrompt.cs
@@ -354,7 +354,7 @@ namespace Microsoft.PowerShell
         /// <param name="fieldEchoOnPrompt">True to echo user input.</param>
         /// <param name="listInput">True if the field is a list.</param>
         /// <param name="endListInput">Valid only if listInput is true. set to true if the input signals end of list input.</param>
-        /// <param name="cancelled">True iff the input is canceled, e.g., by Ctrl-C or Ctrl-Break.</param>
+        /// <param name="cancelled">True if-and-only-if the input is canceled, e.g., by Ctrl-C or Ctrl-Break.</param>
         /// <returns>Processed input string to be converted with LanguagePrimitives.ConvertTo.</returns>
         private string PromptReadInput(string fieldPrompt, FieldDescription desc, bool fieldEchoOnPrompt,
                         bool listInput, out bool endListInput, out bool cancelled)
@@ -484,7 +484,7 @@ namespace Microsoft.PowerShell
         /// !h  prints out field's Quick Help, returns null
         /// All others tilde comments are invalid and return null
         ///
-        /// returns null iff there's nothing the caller can process.
+        /// returns null if-and-only-if there's nothing the caller can process.
         /// </summary>
         /// <param name="input"></param>
         /// <param name="desc"></param>
diff --git a/src/System.Management.Automation/engine/AutomationEngine.cs b/src/System.Management.Automation/engine/AutomationEngine.cs
index cc1ca2f5a..592796d5b 100644
--- a/src/System.Management.Automation/engine/AutomationEngine.cs
+++ b/src/System.Management.Automation/engine/AutomationEngine.cs
@@ -86,7 +86,7 @@ namespace System.Management.Automation
         /// Compile a piece of text into a parse tree for later execution.
         /// </summary>
         /// <param name="script">The text to parse.</param>
-        /// <param name="addToHistory">True iff the scriptblock will be added to history.</param>
+        /// <param name="addToHistory">True if-and-only-if the scriptblock will be added to history.</param>
         /// <returns>The parse text as a parsetree node.</returns>
         internal ScriptBlock ParseScriptBlock(string script, bool addToHistory)
         {
diff --git a/src/System.Management.Automation/engine/CoreAdapter.cs b/src/System.Management.Automation/engine/CoreAdapter.cs
index 55486c674..980d093f8 100644
--- a/src/System.Management.Automation/engine/CoreAdapter.cs
+++ b/src/System.Management.Automation/engine/CoreAdapter.cs
@@ -5440,7 +5440,7 @@ namespace System.Management.Automation
             }
 
             XmlNodeList nodeChildren = node.ChildNodes;
-            // nodeChildren will not be null as we already verified iff the node has children.
+            // nodeChildren will not be null as we already verified that the node has children.
             if ((nodeChildren.Count == 1) && (nodeChildren[0].NodeType == XmlNodeType.Text))
             {
                 return node.InnerText;
diff --git a/src/System.Management.Automation/engine/ICommandRuntime.cs b/src/System.Management.Automation/engine/ICommandRuntime.cs
index 4fd0c0061..49b1104e0 100644
--- a/src/System.Management.Automation/engine/ICommandRuntime.cs
+++ b/src/System.Management.Automation/engine/ICommandRuntime.cs
@@ -457,11 +457,11 @@ namespace System.Management.Automation
         /// It may be displayed by some hosts, but not all.
         /// </param>
         /// <param name="yesToAll">
-        /// true iff user selects YesToAll.  If this is already true,
+        /// true if-and-only-if user selects YesToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return true.
         /// </param>
         /// <param name="noToAll">
-        /// true iff user selects NoToAll.  If this is already true,
+        /// true if-and-only-if user selects NoToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return false.
         /// </param>
         /// <returns>
@@ -592,11 +592,11 @@ namespace System.Management.Automation
         /// the default option selected in the selection menu is 'No'.
         /// </param>
         /// <param name="yesToAll">
-        /// true iff user selects YesToAll.  If this is already true,
+        /// true if-and-only-if user selects YesToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return true.
         /// </param>
         /// <param name="noToAll">
-        /// true iff user selects NoToAll.  If this is already true,
+        /// true if-and-only-if user selects NoToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return false.
         /// </param>
         /// <exception cref="System.Management.Automation.PipelineStoppedException">
diff --git a/src/System.Management.Automation/engine/MshCommandRuntime.cs b/src/System.Management.Automation/engine/MshCommandRuntime.cs
index 427929c3e..9d59d02cb 100644
--- a/src/System.Management.Automation/engine/MshCommandRuntime.cs
+++ b/src/System.Management.Automation/engine/MshCommandRuntime.cs
@@ -1483,7 +1483,7 @@ namespace System.Management.Automation
         /// <see cref="System.Management.Automation.ShouldProcessReason"/>
         /// are returned.
         /// </param>
-        /// <remarks>true iff the action should be performed</remarks>
+        /// <remarks>true if-and-only-if the action should be performed</remarks>
         /// <exception cref="System.Management.Automation.PipelineStoppedException">
         /// The pipeline has already been terminated, or was terminated
         /// during the execution of this method.
@@ -1783,11 +1783,11 @@ namespace System.Management.Automation
         /// the default option selected in the selection menu is 'No'.
         /// </param>
         /// <param name="yesToAll">
-        /// true iff user selects YesToAll.  If this is already true,
+        /// true if-and-only-if user selects YesToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return true.
         /// </param>
         /// <param name="noToAll">
-        /// true iff user selects NoToAll.  If this is already true,
+        /// true if-and-only-if user selects NoToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return false.
         /// </param>
         /// <exception cref="System.Management.Automation.PipelineStoppedException">
@@ -1830,11 +1830,11 @@ namespace System.Management.Automation
         /// It may be displayed by some hosts, but not all.
         /// </param>
         /// <param name="yesToAll">
-        /// true iff user selects YesToAll.  If this is already true,
+        /// true if-and-only-if user selects YesToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return true.
         /// </param>
         /// <param name="noToAll">
-        /// true iff user selects NoToAll.  If this is already true,
+        /// true if-and-only-if user selects NoToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return false.
         /// </param>
         /// <exception cref="System.Management.Automation.PipelineStoppedException">
diff --git a/src/System.Management.Automation/engine/cmdlet.cs b/src/System.Management.Automation/engine/cmdlet.cs
index b2b63d364..742224c21 100644
--- a/src/System.Management.Automation/engine/cmdlet.cs
+++ b/src/System.Management.Automation/engine/cmdlet.cs
@@ -1311,11 +1311,11 @@ namespace System.Management.Automation
         /// It may be displayed by some hosts, but not all.
         /// </param>
         /// <param name="yesToAll">
-        /// true iff user selects YesToAll.  If this is already true,
+        /// true if-and-only-if user selects YesToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return true.
         /// </param>
         /// <param name="noToAll">
-        /// true iff user selects NoToAll.  If this is already true,
+        /// true if-and-only-if user selects NoToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return false.
         /// </param>
         /// <exception cref="System.Management.Automation.PipelineStoppedException">
@@ -1451,11 +1451,11 @@ namespace System.Management.Automation
         /// the default option selected in the selection menu is 'No'.
         /// </param>
         /// <param name="yesToAll">
-        /// true iff user selects YesToAll.  If this is already true,
+        /// true if-and-only-if user selects YesToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return true.
         /// </param>
         /// <param name="noToAll">
-        /// true iff user selects NoToAll.  If this is already true,
+        /// true if-and-only-if user selects NoToAll.  If this is already true,
         /// ShouldContinue will bypass the prompt and return false.
         /// </param>
         /// <exception cref="System.Management.Automation.PipelineStoppedException">
diff --git a/src/System.Management.Automation/engine/pipeline.cs b/src/System.Management.Automation/engine/pipeline.cs
index e19bf3be8..91bf43591 100644
--- a/src/System.Management.Automation/engine/pipeline.cs
+++ b/src/System.Management.Automation/engine/pipeline.cs
@@ -1441,7 +1441,7 @@ namespace System.Management.Automation.Internal
         /// </summary>
         /// <param name="e">Error which terminated the pipeline.</param>
         /// <param name="command">Command against which to log SecondFailure.</param>
-        /// <returns>True iff the pipeline was not already stopped.</returns>
+        /// <returns>True if-and-only-if the pipeline was not already stopped.</returns>
         internal bool RecordFailure(Exception e, InternalCommand command)
         {
             bool wasStopping = false;
diff --git a/src/System.Management.Automation/namespaces/CoreCommandContext.cs b/src/System.Management.Automation/namespaces/CoreCommandContext.cs
index 5c62ed6fa..9ed0e8be9 100644
--- a/src/System.Management.Automation/namespaces/CoreCommandContext.cs
+++ b/src/System.Management.Automation/namespaces/CoreCommandContext.cs
@@ -551,7 +551,7 @@ namespace System.Management.Automation
         /// <param name="target">
         /// Name of the target resource being acted upon
         /// </param>
-        /// <remarks>true iff the action should be performed</remarks>
+        /// <remarks>true if-and-only-if the action should be performed</remarks>
         /// <exception cref="PipelineStoppedException">
         /// The ActionPreference.Stop or ActionPreference.Inquire policy
         /// triggered a terminating error.  The pipeline failure will be
@@ -577,7 +577,7 @@ namespace System.Management.Automation
         /// Name of the target resource being acted upon
         /// </param>
         /// <param name="action">What action was being performed.</param>
-        /// <remarks>true iff the action should be performed</remarks>
+        /// <remarks>true if-and-only-if the action should be performed</remarks>
         /// <exception cref="PipelineStoppedException">
         /// The ActionPreference.Stop or ActionPreference.Inquire policy
         /// triggered a terminating error.  The pipeline failure will be
@@ -616,7 +616,7 @@ namespace System.Management.Automation
         /// if the user is prompted whether or not to perform the action.
         /// It may be displayed by some hosts, but not all.
         /// </param>
-        /// <remarks>true iff the action should be performed</remarks>
+        /// <remarks>true if-and-only-if the action should be performed</remarks>
         /// <exception cref="PipelineStoppedException">
         /// The ActionPreference.Stop or ActionPreference.Inquire policy
         /// triggered a terminating error.  The pipeline failure will be
@@ -665,7 +665,7 @@ namespace System.Management.Automation
         /// <see cref="System.Management.Automation.ShouldProcessReason"/>
         /// are returned.
         /// </param>
-        /// <remarks>true iff the action should be performed</remarks>
+        /// <remarks>true if-and-only-if the action should be performed</remarks>
         /// <exception cref="PipelineStoppedException">
         /// The ActionPreference.Stop or ActionPreference.Inquire policy
         /// triggered a terminating error.  The pipeline failure will be
diff --git a/src/System.Management.Automation/singleshell/config/MshSnapinInfo.cs b/src/System.Management.Automation/singleshell/config/MshSnapinInfo.cs
index 643e649ca..df01b0536 100644
--- a/src/System.Management.Automation/singleshell/config/MshSnapinInfo.cs
+++ b/src/System.Management.Automation/singleshell/config/MshSnapinInfo.cs
@@ -407,8 +407,9 @@ namespace System.Management.Automation
         }
 
         /// <summary>
-        /// Returns true if the PSSnapIn Id is valid. A PSSnapIn is valid iff it contains only
-        /// "Alpha Numeric","-","_","." characters.
+        /// Returns true if the PSSnapIn Id is valid. A PSSnapIn is valid
+        /// if-and-only-if it contains only "Alpha Numeric","-","_","."
+        /// characters.
         /// </summary>
         /// <param name="psSnapinId">PSSnapIn Id to validate.</param>
         internal static bool IsPSSnapinIdValid(string psSnapinId)
@@ -422,8 +423,8 @@ namespace System.Management.Automation
         }
 
         /// <summary>
-        /// Validates the PSSnapIn Id. A PSSnapIn is valid iff it contains only
-        /// "Alpha Numeric","-","_","." characters.
+        /// Validates the PSSnapIn Id. A PSSnapIn is valid if-and-only-if it
+        /// contains only "Alpha Numeric","-","_","." characters.
         /// </summary>
         /// <param name="psSnapinId">PSSnapIn Id to validate.</param>
         /// <exception cref="PSArgumentException">