Update 4 5 isosurface

4-5-isosurface.md

@@ -5,7 +5,7 @@
 ![](img/4-5-isosurface.png)
 
 > NOTE:  
-> In order to visualize wind speed, you need not only u & v components of wind vectors, but also the vertical component in your dataset.  
+> In order to visualize wind speed, you need both u and v components of wind vectors in your dataset.  
 > For the terms & names of UI components, refer to _[UI Components](3-1-ui-components)_.
 
 ##### 1. Open data file.