In the first place, I would leave out the Dative case. It confuses the
plurals; and, besides, nobody ever knows when he is in the Dative case,
except he discover it by accident – and then he does not know when or where
it was that he got into it, or how long he has been in it, or how he is
going to get out of it again. The Dative case is but an ornamental folly --
it is better to discard it