Breakdown of A mí no me engañas: sé que estás triste.
no
no / not
estar
to be (location/state)
triste
sad
a
personal a (marks a person object)
que
that (relative pronoun, conjunction)
saber
to know (facts, information)
me
to me / myself (reflexive) / me (direct object)
mí
me
engañar
to cheat on; to deceive, to trick, to fool
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