The verb volar (to fly) is irregular, (o) changes to (ue) in the present tense (with the exception of nosotros and vosotros).

The congugation of the verb volar is shown in the table below.

volar

			

				
 
				
volar
				
 
			
			

				
yo
				
 vuelo
				
(I fly)
			
			

				
tú
				
 vuelas
				
(you fly)
			
			

				
Ud./él/ella
				
 vuela
				
(you fly)
			
			

				
nosotros (as)
				
 volamos
				
(we fly)
			
			

				
vosotros (as)
				
 voláis
				
(you fly)
			
			

				
Uds./ellos/ellas
				
 vuelan
				
(they fly)
			
		

The verbs mostrar (to show), and dormir (to sleep) follow the same pattern as volar, (o) changes to (ue) in the present tense (with the exception of nosotros and vosotros).

The congugation of the verb mostrar, and dormir is shown in the table below.

mostrar dormir

			

				
 
				
mostrar
				
dormir
			
			

				
yo
				
 muestro
				
 duermo
			
			

				
tú
				
 muestras
				
 duermes
			
			

				
Ud./él/ella
				
 muestra
				
 duerme
			
			

				
nosotros (as)
				
 mostramos
				
 dormimos
			
			

				
vosotros (as)
				
 mostráis
				
 dormís
			
			

				
Uds./ellos/ellas
				
 muestran
				
 duermen
			
		

Note: yo = I, tú = you (informal), usted (Ud.) = you (formal),
él = he, ella = she, nosotros = we (males), nosotras = we
(females), vosotros = you guys (informal, males), vosotras = 
you guys (informal, females),  ellos = they (males), ellas = 
they (females), ustedes (Uds.) = you all (formal)

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