gistfile1.php

<?php

trait AbstractSpeak
{
    abstract protected function speak($string);
}

trait PrintSpeak
{
    protected function speak($string)
    {
        print "$string\n";
    }
}

trait Hello
{
    use AbstractSpeak;

    public function sayHello()
    {
        $this->speak("hello");
    }
}

trait Hey
{
    use AbstractSpeak;

    public function sayHey()
    {
        $this->speak("hey");
    }
}

class Hoge
{
    use Hello;
    use Hey;
    use PrintSpeak;
}

$hoge = new Hoge();
$hoge->sayHello();
$hoge->sayHey();