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I noticed that sometimes the pronunciation changes when combining words. An other example is 不死斬り (ふしぎり) and 腹切り (はらきり); both 斬り and 切り are pronounced きり independently but only in 不死斬り is 斬り pronounced ぎり and not きり.

Is there a rule for that?

My assumption is that it depends on the ending sound of the first word. If it ends with a i sound (ni,shi,etc) then they lead to dakuten (") on the following syllable.

marked as duplicate by l'électeur, broccoli forest, naruto, Blavius, snailboat Apr 23 at 15:59

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