Idiomatic LINQ way to access both object and an object's property? [Answered]

var list = new List<string>();

foreach (Item item in items)
{
  foreach (string thing in item.Things)
  {
    list.Add($"{thing} + {item.OtherProperty}");
  }
}

return list;

var list = new List<string>();

foreach (Item item in items)
{
  foreach (string thing in item.Things)
  {
    list.Add($"{thing} + {item.OtherProperty}");
  }
}

return list;