Same name space can directly be called

// Same name space class can directly be called without use

 <?php

namespace Test\Collection; 

class First{}

<?php

namespace Test\Collection; 

class Second{

  public function test() {

    $a = new First();

  }

}

https://stackoverflow.com/questions/34528396/php-same-namespace-for-several-classes

// Call two clasess from same name space in a different name space

<?php

use Test\Collection\First;
use Test\Collection\Second;

$first = new First();
$second = new Second();
Or:
<?php

use Test\Collection;

$first = new Collection\First();
$second = new Collection\Second();