But, "VBN(killed)" is indeed separable into two finegrained tree fragments of "VBN(killed:active)" and "VBN(killed:passive)" 1 .
"VBN(killed:active)" appears 5 times with "koroshita" and 1 time with "korosareta"; and "VBN(killed:passive)" appears 1 time with "koroshita" and 3 times with "korosareta".