Verbs:
* Abrir: To open
* Acostar: To lie down, to go to bed
* Añadir: To add
* Aparecer: To appear
* Aprender: To learn
* Asistir: To attend
* Comer: To eat
* Conducir: To drive
* Comprar: To buy
* Creer: To believe
* Decir: To say, to tell
* Dormir: To sleep
* Escribir: To write
* Escuchar: To listen
* Enviar: To send
* Hablar: To speak
* Ir: To go
* Leer: To read
* Llegar: To arrive
* Mirar: To look at
* Morir: To die
* Pedir: To ask for
* Pensar: To think
* Perder: To lose
* Poder: To be able to
* Poner: To put, to place
* Probar: To try, to taste
* Recibir: To receive
* Repetir: To repeat
* Saber: To know
* Salir: To go out
* Servir: To serve
* Seguir: To follow
* Tener: To have
* Traducir: To translate
* Trabajar: To work
* Usar: To use
* Ver: To see
* Vivir: To live
Nouns:
* Círculo: Circle
* Humor: Humor
* Misterio: Mystery
* Partir: Departure
* Regalo: Gift
* Teatro: Theater
* Vuelo: Flight
Adjectives:
* Interior: Inner, internal
* Exterior: Outer, external
* Superior: Superior
* Inferior: Inferior
* Posterior: Posterior
* Anterior: Anterior
* Regular: Regular
These are just a few examples. There are many more Spanish words that end in "-ir." Keep in mind that the "-ir" ending is primarily associated with verbs, but some nouns, adjectives, and even adverbs can also end in "-ir."