regular expression does not match the beginning word

 0 I was trying out some regular expressions shown in NLPclass using regextester website.I used the following string The other one,the blithe one  When I used the regex [^a-zA-Z][Tt]he[^a-zA-Z] , only the word 'the' after the comma got matched. But when I put a space in front of the whole sentence( just before 'The'), the two words 'The' at the beginning and 'the' after comma got matched. I cannot understand why the regex failed to do the match for 'The' at the start of sentence ,why do I have to introduce another character. In the course video,Prof.J gets the correct results because there was a string in the previous line.If there wasn't,then 'The' at the beginning of the sentence won't match. asked 10 Mar '12, 00:05 aikid 2.9k●5●43

 2 It's because you tell it to match a character before T. When it says don't match these characters it is actually saying 'match a character but not one of these,' hence putting a space in front means the condition is satisfied. answered 10 Mar '12, 00:15 fnenu 811●11
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