fix typos

Author: jayzzhou-thu

README.md

@@ -9,52 +9,52 @@ Contributed by Jie Zhou, Ganqu Cui, Zhengyan Zhang and Yushi Bai.
 <tr><td colspan="2"><a href="#survey-papers">1. Survey</a></td></tr> 
 <tr><td colspan="2"><a href="#models">2. Models</a></td></tr>
 <tr>
-    <td>&emsp;<a href="#basic-models">2.1 Basic Models</a></td>
+    <td>&ensp;<a href="#basic-models">2.1 Basic Models</a></td>
     <td>&ensp;<a href="#graph-types">2.2 Graph Types</a></td>
 </tr>
 <tr>
-    <td>&emsp;<a href="#pooling-methods">2.3 Pooling Methods</a></td>
+    <td>&ensp;<a href="#pooling-methods">2.3 Pooling Methods</a></td>
     <td>&ensp;<a href="#analysis">2.4 Analysis</a></td>
 </tr>
 <tr>
-    <td>&emsp;<a href="#efficiency">2.5 Efficiency</a></td>
-    <td>&emsp;<a href="#explainability">2.6 Explainability</a></td>
+    <td>&ensp;<a href="#efficiency">2.5 Efficiency</a></td>
+    <td>&ensp;<a href="#explainability">2.6 Explainability</a></td>
 </tr>
 <tr><td colspan="2"><a href="#applications">3. Applications</a></td></tr> 
 <tr>
-    <td>&emsp;<a href="#physics">3.1 Physics</a></td>
+    <td>&ensp;<a href="#physics">3.1 Physics</a></td>
     <td>&ensp;<a href="#chemistry-and-biology">3.2 Chemistry and Biology</a></td>
 </tr> 
 <tr>
-    <td>&emsp;<a href="#knowledge-graph">3.3 Knowledge Graph</a></td>
+    <td>&ensp;<a href="#knowledge-graph">3.3 Knowledge Graph</a></td>
     <td>&ensp;<a href="#recommender-systems">3.4 Recommender Systems</a></td>
 </tr>
 <tr>
-    <td>&emsp;<a href="#computer-vision">3.5 Computer Vision</a></td>
+    <td>&ensp;<a href="#computer-vision">3.5 Computer Vision</a></td>
     <td>&ensp;<a href="#natural-language-processing">3.6 Natural Language Processing</a></td>
 </tr> 
 <tr>
-    <td>&emsp;<a href="#generation">3.7 Generation</a></td>
+    <td>&ensp;<a href="#generation">3.7 Generation</a></td>
     <td>&ensp;<a href="#combinatorial-optimization">3.8 Combinatorial Optimization</a></td>
 </tr> 
 <tr>
-    <td>&emsp;<a href="#adversarial-attack">3.9 Adversarial Attack</a></td>
+    <td>&ensp;<a href="#adversarial-attack">3.9 Adversarial Attack</a></td>
     <td>&ensp;<a href="#graph-clustering">3.10 Graph Clustering</a></td>
 </tr>
 <tr>
-    <td>&emsp;<a href="#graph-classification">3.11 Graph Classification</a></td>
+    <td>&ensp;<a href="#graph-classification">3.11 Graph Classification</a></td>
     <td>&ensp;<a href="#reinforcement-learning">3.12 Reinforcement Learning</a></td>
 </tr>
 <tr>
-    <td>&emsp;<a href="#traffic-network">3.13 Traffic Network</a></td>
+    <td>&ensp;<a href="#traffic-network">3.13 Traffic Network</a></td>
     <td>&ensp;<a href="#few-shot-and-zero-shot-learning">3.14 Few-shot and Zero-shot Learning</a></td>
 </tr>
 <tr>
-    <td>&emsp;<a href="#program-representation">3.15 Program Representation</a></td>
+    <td>&ensp;<a href="#program-representation">3.15 Program Representation</a></td>
     <td>&ensp;<a href="#social-network">3.16 Social Network</a></td>
 </tr> 
 <tr>
-    <td>&emsp;<a href="#graph-matching">3.17 Graph Matching</a></td>
+    <td>&ensp;<a href="#graph-matching">3.17 Graph Matching</a></td>
     <td>&ensp;<a href="#computer-network">3.18 Computer Network</a></td>
 </tr>
 </table>