$re = '/link to (?<keyword>[a-z ]+) from (?<name>[a-z ]+)(?=shared)?(?<time>[a-z]+)?/i';
$str = 'link to connect link from sandeep akula
link to sharepoint git from sapna
link to sharepoint git from sapna grover shared yesterday
sharepoint git link form sapna shared yesterday';
preg_match_all($re, $str, $matches, PREG_SET_ORDER, 0);
// Print the entire match result
var_dump($matches);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for PHP, please visit: http://php.net/manual/en/ref.pcre.php