Regex to match first word in sentence

Question

I am looking for a regex that matches first word in a sentence excluding punctuation and white space. For example: \"This\" in \"This is a sentence.\" and \"First\" in \"First,

Answer 1

[a-z]+

This should be enough as it will get the first a-z characters (assuming case-insensitive).

In case it doesn't work, you could try [a-z]+\b, or even ^[a-z]\b, but the last one assumes that the string starts with the word.