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QUICK ANSWER
"En" is a form of "en", a preposition which is often translated as "in". "A.T." is an abbreviation which is often translated as "OT". Learn more about the difference between "en" and "A.T." below.
en()
A preposition is a word that indicates the relationship between a noun and another word (e.g., He ran through the door.).
A.T.()
An abbreviation is the shortened form of a word or group of words (e.g., "UFO" = "unidentified flying object"; "p." = "page").
a. OT
La historia de Sansón y Dalila figura en el A.T.The story of Samson and Delilah appears in the OT.
