tras PREPOSITION after
Tras is an alternative way of saying after – después de – and tends to be used in writing more than in speech, except in some set phrases:
Salimos corriendo tras ella. We ran out after her.
Tras unos días de vacaciones volvió a su trabajo. After a few days’ vacation she went back to work.
To emphasize something being done repeatedly, you put tras between two periods of time:
Viene ganando año tras año. Year after year he’s won.
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