qiáo shé yīn 
		retroflex
consonants zh, ch, sh, r produced on the back of the tongue
		 
		
		
														
		
		
			 
		
				
		
			píng shé yīn 
		alveolar
consonants z, c, s produced with the tip of the tongue on the alveolar ridge
		 
		
		
		
		
					
				
		
			qiào shé yīn 
		retroflex sound (e.g. in Mandarin zh, ch, sh, r)
		 
		
		
														
		
		
			 
		
				
		
			shé yīn 
		coronal consonants of Middle Chinese