<?php
 
error_reporting(-1);
 
$text     = <<<EOF
Пocтaвкa мяco гoвядины, бecкостнoe для нужд 
государственного бюджетного учреждения здравоохранения 
Республики Башкортостан Инфекционная клиническая больница 
№ 4 города Уфа 
EOF
;
 
$word     = explode(" ", $text);
$regexp   = '/[а-яё]*[a-z]{1}\\w*/ui';
$regError = '/([a-z])/ui';
 
$match    = [];
 
foreach($word as $words) {
		if(preg_match($regexp, $words, $match)) {
		   $error = preg_replace($regError, '[$1]', $match[0]);
		   echo "Буквы заменены в слове {$match[0]}: {$error}\n";
	}
}

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