\ba Unicode word boundary
applethe literal text apple (case sensitive) \ba Unicode word boundary
.*?any Unicode character (except for line terminators), repeated any number of times
\ba Unicode word boundary
eachthe literal text each (case sensitive) \ba Unicode word boundary
Negative Lookahead(?! box) boxthe literal text box (case sensitive) g modifier: global. Finds all matches instead of stopping after the first
m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string