Thank you for your answer. I must confess, that at the time when reading your reply to 'Substitution don't work' I didn't understand this Updat 3, especially the meaning of the " ", and I had no clue what these [[ should mean. As I am just at the beginning with perl, I thought these characters are some special codes I just don't know yet, because there are so many characters with special meanings in perl. Now (that means today), after all the friendly posts of the humble Monks and after studying these posts and trying to understand what I read I finally have understood that between the " " that is the code and that the other stuff is meant to explain how the regex works. I eventually succeded in running this update 3 and I could see how it works. I agree, I should have tried harder the first time when I read this update 3. But for my defence I have to say that for experienced Monks like you all this is obvious, but for a newbie like me (72 years old :-) and as a German always fighting with my school English) even the obvious is sometimes not easy. I have learned a lot from you and the other monks since I have started here and I'm greatful to this community.