diff --git a/book/syntax_exercises/009.md b/book/syntax_exercises/009.md
index 077984c..a9adf32 100644
--- a/book/syntax_exercises/009.md
+++ b/book/syntax_exercises/009.md
@@ -29,7 +29,7 @@ The syntax used for creation equations is TeX, a markup language for math. It's
 $$ E = m \ccdot c^2 $$
 ```
 
-4. Check whether the equations renders correctly by clicking `preview`. Note that all ill-formatted equation are indicated in red, i.e. $\red{\text{\ccdot}}$
+4. Check whether the equations renders correctly by clicking `preview` if you're making this edit in the GitHub single file editor. Make sure you already defined the file type as `<title>.md` to enable rendering. Note that all ill-formatted equation are indicated in red, i.e. $\red{\text{\ccdot}}$
 
 5. As an alternative you try and use the 'math directive'. This will have the same results + adds a equation number which can be used for referencing (refer to [Exercise 11](011.md)):
 
@@ -39,7 +39,7 @@ v = a \cdot t
 ```
 ````
 
-6. Click on `preview` again. Note that these equations don't render. That's because the 'math directive' is a MyST feature (an extension of markdown), which is not supported by the GitHub previewer that only support markdown.
+6. Click on `preview` again. Note that these equations don't render. That's because these 'directives' is a MyST feature (an extension of markdown), which is not supported by the GitHub previewer that only support markdown.
 
 7. Now, add an inline equation by enclosing the equation with single dollar signs. Try this example: