Remind syntax

Author: Bowen-Guo-Microsoft

articles/machine-learning/algorithm-module-reference/execute-r-script.md

@@ -123,6 +123,9 @@ Datasets stored in the designer are automatically converted to an R data frame w
 
 1. In the **R script** text box, type or paste valid R script.
 
+    > [!NOTE]
+    > Please be very careful when writing your script and makes sure there is no syntax error, such as using a un-declared variable or a un-imported module or function. Also pay extra attentions to the pre-installed package list in the end of this document. To use packages that are not listed, please install them in your script such as `install.packages("zoo",repos = "http://cran.us.r-project.org")`
+    
     To help you get started, the **R Script** text box is pre-populated with sample code, which you can edit or replace.
 
     ```R