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"Tú" is a form of "tú", a pronoun which is often translated as "you". "Fecha" is a form of "fecha", a noun which is often translated as "date". Learn more about the difference between "tú" and "fecha" below.
tú(
too
)A pronoun is a word that stands in for a noun (e.g., she).
1. (informal) (second person singular)
A word or phrase used to refer to the second person informal “tú” by their conjugation or implied context (e.g., How are you?).
la fecha(
feh
-
chah
)A feminine noun is almost always used with feminine articles and adjectives (e.g., la mujer bonita, la luna llena).
las fechas
A plural noun indicates that there is more than one person, place, thing, or idea.
a. time of the year 
Las fiestas de Navidad son fechas alegres para la mayoría.Christmas is a happy time of the year for most.