You can add comments to expressions. Both single line and multi-line comments can be added to expressions.
To add a single line comment to an expression, add // where you want the comment to begin. All of the characters after the // to the end of the line will be included in the comment.
To add a multi-line comment to an expression, add /* where you want the comment to begin. You can add multiple lines to the comment. To close the comment, add */ to the end of the comment. You can continue the expression after the comment.