Noun and の adjective
こうご
彼女は二種類の味のアイスクリームを交互に舐めた。
She alternately licked two kinds of ice cream.
You mix, then you go mutual, then you mix, and then you go mutual. Alternately, you could go mix again?
This is a jukugo word that uses the on'yomi readings of the kanji. You should be able to read this on your own.