public function actionPlay()
	{
		static $levels=array(
			'10'=>'Easy game; you are allowed 10 misses.',
			'5'=>'Medium game; you are allowed 5 misses.',
			'3'=>'Hard game; you are allowed 3 misses.',
		);

		// if a difficulty level is correctly chosen
		if(isset($_POST['level']) && isset($levels[$_POST['level']]))
		{
			$this->word=$this->generateWord();
			$this->guessWord=str_repeat('_',strlen($this->word));
			$this->level=$_POST['level'];
			$this->misses=0;
			$this->setPageState('guessed',null);
			// show the guess page
			$this->render('guess');
		}
		else
		{
			$params=array(
				'levels'=>$levels,
				// if this is a POST request, it means the level is not chosen
				'error'=>Yii::app()->request->isPostRequest,
			);
			// show the difficulty level page
			$this->render('play',$params);
		}
	}