write + that's just how it is
kaku mono da
that's just how it is; you really should; used to do
人は誰でも間違えるものだ。
hito wa dare demo machigaeru mono da.
Everyone makes mistakes, that's just how people are. neutral
子供のころ、よくこの川で泳いだものだ。
kodomo no koro, yoku kono kawa de oyoida mono da.
When I was a kid, I used to swim in this river all the time. neutral