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"Erre" is a form of "erre", a noun which is often translated as "r". "I" is a noun which is often translated as "i". Learn more about the difference between "erre" and "i" below.
la erre(
eh
-
rreh
)A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
la i(
ee
)A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).