Parentheses group parts of regular expressions together into grouped subexpressions that you can treat as a single unit. For example, the regular expression "ha" specifies to match a single occurrence of the string. The regular expression "(ha)+" matches one or more instances of "ha".

In the following example, you use the regular expression "B(ha)+" to match the letter "B" followed by one or more occurrences of the string "ha":

<cfset IndexOfOccurrence=REFind("B(ha)+", "hahaBhahahaha")>
<!--- The value of IndexOfOccurrence is 5 --->

You can use the special character | in a subexpression to create a logical "OR". You can use the following regular expression to search for the word "jelly" or "jellies":

<cfset IndexOfOccurrence=REFind("jell(y|ies)", "I like peanut butter and jelly">
<!--- The value of IndexOfOccurrence is 26--->