year 5 = from 22 september 1796 - up to and including 21 september 1797
There are several good online convertors
http://www.napoleon.org:81/en/essential_napoleon/calendar/index.asp (English)
http://nl.wikipedia.org/wiki/Franse_Republikeinse_Kalender/Y1 (Dutch - French)
The full translation of the marriage cert
Marriage of Josephus Modde and Amelia De Smet - Zegelsem 29/10/1818
The year 1818
The 29th October at 3 o’clock in the afternoon, before us Jean Baptiste Coman, mayor, officer of the civil registration of the municipality Zegelsem, province East Flanders, have appeared Josephus Modde, 36 years old, born at Opbrakel the 1th October 1782, farmer of profession, adult son of the late Jacobus and the late Catharina De Temmerman, both deceased in Opbrakel and in Zegelsem respectively on the date 16 frimaire year 10 and 18 September 1817, as stated in the death certificates, the first delivered by the mayor of Opbrakel and the second held in the town hall of this place, widower of Catharina Van Der Meulen, deceased in Opbrakel the 18th April last, as stated in the death certificate delivered by the mayor of Opbrakel, one part.
And Amelia De Smet, born in Strijpen the 9th March 1788, , 30 years old, farmer, living in Zegelsem, daughter of the still living Jean Baptiste, consenting, as stated in the power of attorney executed at Velzeke the 24th of this month October, properly registered at Zottegem by Lamanberg ? (surnumeraire / supernumerary ?), the same day , 134 R.G. 5, at the rate permitted by the law, wich power of attorney will be added to this present deed; and from de late Joanna Catharina Hanssens, deceased in Strijpen the 19th July 1792 as stated in the death certificate delivered by the mayor of Strijpen, widow of Francies Van Pevenaege, deceased in Zegelsem the 27th December last. The other part.
Which appearers have requested us to proceed with the celebration of the marriage devised between them, and of which the publication already have been done before de main entrance of our town hall and also at Opbrakel respectively at the 11th and 18th of this month October each time at 10 o’clock in the morning, no opposition to this marriage being reported to us, doing justice to their request, after the reading to the appearers by us off alle the abovementioned documents and of chapter six entitled The Marriage, we have asked the future groom and future bride wether they want to take each other as husband an as wife, each of them, individually, responded with Yes, we declared in the name of the law that Josephus Modde and Amelia De Smet are united in marriage. Of which we have drawn up this act in the presence of Josephus De Prez, 47 years old, farmer, living in Nederbrakel, Charles Van Den Abeele, 38 years old, farmer, living in Erwtegem, Jean Baptiste Van Der Hauwert, 24 years old, clogs maker and Jean Baptiste Sera, 30 years old, innkeeper, living in Zegelsem, who have declared not being relatives nor friends of the appearing parties, and after the reading they have signed the present act with us and the bride, except the first witness and the groom who have declared not being able to write.