<?php
 
    function properCase( $string ) {	
		$ignorar = array( 'do', 'dos', 'da', 'das', 'de' );
		$array = explode(' ', strtolower( $string ) );
		$out = '';
		foreach ($array as $ar) {
           $out .= ( in_array ( $ar, $ignorar ) ? $ar : ucfirst( $ar ) ).' ';
		}
		return trim( $out );
    }
 
	echo properCase( 'PORTO DE GALINHAS' ).PHP_EOL;
	echo properCase( 'HOSPITAL DOS PLANTADORES DE CANA' ).PHP_EOL;
	echo properCase( 'rua do vergueiRO' ).PHP_EOL;

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