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"Parir" is an intransitive verb which is often translated as "to give birth", and "dar a luz" is an intransitive verb phrase which is also often translated as "to give birth". Learn more about the difference between "parir" and "dar a luz" below.
parir(
pah
-
reer
)An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
1. (to birth)
a. to give birth  (woman)
Tengo que irme corriendo al hospital porque mi esposa está pariendo.I have to rush to the hospital because my wife is giving birth.
b. to have a baby  (woman)
En un mismo año se casó y parió.She got married and had a baby the same year.
d. to foal  (mare or jenny)
El veterinario llegó cuando la yegua estaba pariendo.The veterinarian arrived when the mare was foaling.
A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
2. (to birth)
a. to give birth to 
Ahí donde la ves, tan pequeña y tan poca cosa, ha parido cinco hijos.Believe it or not, thin and small as she is, she's given birth to five children.
c. to bear 
Una vaca suele parir un solo ternero cada vez.A cow usually only bears one calf at a time.
a. to produce 
Para parir una novela de estas características hace falta mucho tiempo y dedicación.In order to produce a novel of such characteristics you need a lot of time and dedication.
b. to come up with 
Nos costó parir la idea, pero ahí está.It wasn't easy for us to come up with the idea, but there it is.
dar a luz(  
dahr
ah
loos
)An intransitive verb phrase is a phrase that combines a verb with a preposition or other particle and does not require a direct object (e.g., Everybody please stand up.).