add descriptor and fix formatting

README.md

@@ -58,7 +58,9 @@ The AraStance dataset contains true and false claims, where each claim is paired
 Arabic
 
 ## Dataset Structure
+
 ### Data Instances
+An example of 'train' looks as follows:
 ```
 {
     'id': '0', 
@@ -68,6 +70,7 @@ Arabic
 
 }
 ```
+
 ### Data Fields
 - `id`: a 'string' feature.
 - `claim`: a 'string' expressing a claim/topic.
@@ -79,6 +82,7 @@ Arabic
                 2: "Discuss",
                 3: "Unrelated",
 ```
+
 ### Data Splits
 |name|instances|
 |----|----:|