"( # first quote, start capture
[\p{Word}\.]+? # One or more word character, or period, LAZY MATCHING
.*? # Zero or more any char, LAZY MATCHING
\b # Word boundary
[\.,?!»]*? # Zero or more punctuation, LAZY MATCHING
)" # stop capture, ending quote
Execution process:
"äöõ "ä õ ü" ï"
# ! is used to denote the current position
# First try for [\p{Word}\.]+?
"ä!
# First try for .*? (empty string)
"ä!
# Not a word boundary, backtrack to .*?
# Second try for .*? (ö)
"äö!
# Not a word boundary, backtrack to .*?
# Third try for .*? (öõ)
"äöõ!
# Word boundary matches
# First try for [\.,?!»]*? (empty string)
"äöõ!
# Quote " not found, backtrack to [\.,?!»]*?
# Can't match any of the characters in [\.,?!»], backtrack to .*?
# Fourth try for .*? (öõ )
"äöõ !
# *** Not a word boundary, backtrack to .*?
# Fifth try for .*? (öõ ")
"äöõ "!
# Word boundary matches
# First try for [\.,?!»]*? (empty string)
"äöõ "!
# Quote " not found, backtrack to [\.,?!»]*?
# Can't match any of the characters in [\.,?!»], backtrack to .*?
# Repeat a few times...
# 10th try for .*?
"äöõ "ä õ ü!
# Word boundary matches
# First try for [\.,?!»]*? (empty string)
"äöõ "ä õ ü!
# Quote is found, match completed
"äöõ "ä õ ü"!