Constructing regex pattern to match sentence

I'm trying to write a regex pattern that will match any sentence that begins with multiple or one tab and/or whitespace. For example, I want my regex pattern to be able to match " hello there I like regex!" but so I'm scratching my head on how to match words after "hello". So far I have this:

    String REGEX = "(?s)(\\p{Blank}+)([a-z][ ])*";
    Pattern PATTERN = Pattern.compile(REGEX);
    Matcher m = PATTERN.matcher("         asdsada  adf adfah.");
    if (m.matches()) {
        System.out.println("hurray!");
    }

Any help would be appreciated. Thanks.

An example regex to match sentences by the definition: "A sentence is a series of characters, starting with at lease one whitespace character, that ends in one of ., ! or ?" is as follows:

\s+[^.!?]*[.!?]

Note that newline characters will also be included in this match.

String regex = "^\\s+[A-Za-z,;'\"\\s]+[.?!]$"

^ means "begins with"
\\s means white space
+ means 1 or more
[A-Za-z,;'"\\s] means any letter, ,, ;, ', ", or whitespace character
$ means "ends with"

If you looking to match all strings starting with a white space you can try using "^\s+*" regular expression.

This tool could help you to test your regular expression efficiently.

http://www.rubular.com/