<?php
error_reporting(-1);
mb_internal_encoding('utf-8');
header("Content-Type: text/html; charset=utf-8");
 
$example = "Я помню чудное мнгнoвернье, переdо мной явилась ты. Как мимолетное видeние, как гeний чистой краcoты. Ты где-то тyт. Тecт. А вот eще парочкa.";
 
function findCorruption($text) {
 
	$regexp = '/([а-яё]*)([a-z]+)([а-яё]*)/ui';
	$brokenWords = [];
	$count = preg_match_all($regexp, $text, $brokenWords, PREG_SET_ORDER);
 
	$result = [];
	foreach ($brokenWords as $word) {
		$result[] = preg_replace($regexp, '$1[$2]$3', $word[0]);
	}
	return $result;
}
 
$test = findCorruption($example);
 
foreach ($test as $mistake) {
	echo "Опечатка в слове: $mistake.\n";
}

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