if you don't mind, if you like, if you're so inclined

nothing

what number, how many (used with a counter) / (used with も) many (used with a counter)

What?, Huh?

what / that thing (used in place of words you can't remember at the moment.)

what

what is this?

是松: a surname

conjunctive form of 待つ, 俟つ: to wait / conjunctive form of 舞う: to dance; to whirl, twirl, swirl

天津風: an Isokaze-class destroyer of the Imperial Japanese Navy; a Kagerō-class destroyer of the Imperial Japanese Navy