#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?s)(?:(?!(?<!\w)\w(?!\w)).)+"
Local $sString = "I need to use regular expressions to draw all the individual letters from the entire sentence, and the result must be in only one group, it can not be a separate group. E.g:" & @CRLF & _
"" & @CRLF & _
"This is an example sentence in which I have two letters: "
Local $sSubst = "\n"
Local $sResult = StringRegExpReplace($sString, $sRegex, $sSubst)
MsgBox($MB_SYSTEMMODAL, "Result", $sResult)
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm