diff --git a/data/modifications.cfg b/data/modifications.cfg
index ad54bc4ce3d..bd0c9d3f887 100644
--- a/data/modifications.cfg
+++ b/data/modifications.cfg
@@ -4,7 +4,7 @@
 [modification]
     id=plan_unit_advance
     name=_"Plan Unit Advance"
-    description=_"When playing a multiplayer game, you do not control what a unit advances if they advances on another player's turn. With this modification you can set what your units advance to beforehand either for a specific unit or for all units of the same type."
+    description=_"When playing a multiplayer game, you do not control what a unit advances to if it advances on another player's turn. With this modification you can set what your units advance to beforehand, either for a specific unit or for all units of the same type."
 
     [options]
         [checkbox]