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"Hache" is a form of "hache", a noun which is often translated as "h". "Efe" is a noun which is often translated as "f". Learn more about the difference between "efe" and "hache" below.
la efe()
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
la hache()
A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).