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"Llovió" is a form of "llovió", a phrase which is often translated as "it rained". "Llovía" is a form of "llover", an impersonal verb which is often translated as "to rain". Learn more about the difference between "llovió" and "llovía" below.
llover(
yoh
-
behr
)An impersonal verb is a verb with no apparent subject (e.g., Llueve en España.).
An intransitive verb is one that does not require a direct object (e.g., The man sneezed.).
a. to rain down on (figurative)
Me llovieron todo tipo de problemas.All sorts of problems rained down on me.