The word 'senio' means nothing. I think you misspelled it, because 'serio' is a word. 'En serio' means 'seriously'.
"En senio" is not a typical English phrase. It could be a misspelling or typo. If you provide more context, I may be able to help determine the intended meaning.
"Retraite" means "retreat" in English.
"Count on my long experience!" is an English equivalent of the French phrase Croyez en ma vieille expérience! The phrase most famous occurs in the film Le roi et l'oiseau ("The King and the Bird") by French animator Paul Grimault (Mar. 23, 1905-Mar. 29, 1994) and translates literally as "Believe in my ancient experience" in English. The pronunciation will be "kra-ye-zaw ma vyeh-yek-spey-ryaws" in French.
Grand-mère (feminine noun) means 'grandmother' in English.
The phrase "el viejo" translates to "the old man" in English.
"The grandparents' house"
Fuiono Senio died in 1997.
Kevin Senio was born on July 6, 1978.
Kevin Senio was born on July 6, 1978.
The population of Palazzuolo sul Senio is 1,234.
John Senio was born on 1982-09-10.
Senio Kelemete was born on 1990-05-10.
NFL player Senio Kelemete is 6'-03''.
"En anglais" is French for "in English".
that
en la mia chillin
Ecrivez en francais
If you mean en la feria then the translation is "at the fair"