GRE group; one word difference at the beginning

1. Gre word:  Benison vs. Venison
   Benison (n): blessing
   Venison (n): meat from a deer.
2. Gre word: Bolster vs. Holster
   Bolster (v): support or reinforce
   Holster (n): a holder carrying a handgun, typically worn on a belt or under the arm.
3. Gre word: Callow vs. Fallow
   Callow (adj): (of a young person) inexperienced and immature
   Fallow (adj): plowed but not sowed; uncultivated

GRE Group : River/Lake/ Sea

1. Archipelago(n): an extensive group of islands
2. Atoll (n): a ring- shaped reef or chain of islands formed of coral
Analogy: ISLAND: ATOLL:: utensil: fork (member and class)