<?php
header("Content-Type: text/plain; charset=utf-8");
error_reporting(E_ALL | E_STRICT);
 
$text = <<<EOF
МУУ ГООУО ОПП по Удмуртинской Области объявляет конкурс на поставку кaнцелярских тoваров на сумму 100500 руб.
EOF;
 
$regex = '/([а-яёА-ЯЁ]+)([a-zA-Z]+)([а-яёА-ЯЁ]*)/u';
 
preg_match_all($regex,$text,$matches);
 
foreach ($matches[0] as $key=>$match) {
    echo 'Опечатка в слове ' . $match . ': ' . $matches[1][$key] . '[' . $matches[2][$key] .
        ']' . $matches[3][$key] . "\n";
}

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