'I thought of a better example for oshiete oite yaru. Say you say in English "Leave the window open." That would be Mado wo akete oite. Just you can't say "I'll leave this told to you." Oku being "to leave (transitive)" as in Soko ni oite ii, "You can leave it there," and Oitetcha iya da ( = oite itte wa iya da ), "Don't leave me here!" (Officially it's romanized ccha and not tcha, but since phonetically ch = t + sh I much prefer "tch" to "cch," which looks like it ought to be pronounced like "kch.")'
And now I am off to get brunch and then study over in Breidenbaugh a little bit more...Kiyomori, Koremori, Munemori...is the mori 森？ And Shigemori and Shigehira - what's the shige? Then, there's Yoritomo and Tomomori...tomo = 友？？ Too many samurai names^^ I wonder if Hiroyuki is a name from back around then or if it's a later creation...hmm.