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"At the end" is a phrase which is often translated as "al final", and "at last" is a phrase which is often translated as "por fin". Learn more about the difference between "at the end" and "at last" below.
at last( 
aht
lahst
)A phrase is a group of words commonly used together (e.g., once upon a time).
1. (finally)
a. por fin 
After driving for 10 hours without stopping, we arrived to Texas at last.Después de manejar por 10 horas sin parar, por fin llegamos a Texas.
b. finalmente 
And, at last, we will be able to hear from our president.Y, finalmente, podremos escuchar a nuestro presidente.
c. al fin 
My kids are all at school, and at last there is peace in my house.Mis hijos están en la escuela, y al fin hay paz en mi casa.