$re = '/Yii::t\((?:[\'"][^\'"]*[\'"],?\s*)*\)/';
$str = 'Yii::t(\'backend\',\'My Profile\')
Yii::t(\'backend\',\'Log Out\')
Yii::t("backend", "Search...")
Yii::t("backend", \'Sounds\')
Yii::t("", \'Sounds\')';
preg_match_all($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