Update 8-knowledge-check.yml

Author: QijieXue

learn-pr/wwl-language/csharp-literals-variables/8-knowledge-check.yml

@@ -16,7 +16,7 @@ durationInMinutes: 3
 quiz:
   title: "Check your knowledge"
   questions:
-  - content: "Which of the following variable names should or must be **avoided**?"
+  - content: "Which of the following variable names should or must be **avoided**?" 
     choices:
     - content: "$DATA"
       isCorrect: true
@@ -59,4 +59,4 @@ quiz:
       explanation: "Correct! The assignment correctly matches the declared data type."
     - content: "`bool x = 'False';`"
       isCorrect: false
-      explanation: "Incorrect. The first problem is that you can't use a single quote to create a `string` literal. The second problem is that you can't set a `bool` to a `string` or `char` literal."
+      explanation: "Incorrect. The first problem is that you can't use a single quote to create a `string` literal. The second problem is that you can't set a `bool` to a `string` or `char` literal."