I was making a Memory type game for my brother but with a little twist to make it interesting while he is working against the clock. And while trying to make pairs of cards for the game I confused my self.
I am a little confused as to what your question is here. With seven colors you cannot nicely divide them into pairs, but it is still possible for each word to have a different color, without any color being missing. Picture it as if all of the words were arranged in a circle, then all the colors just shifted over to the next word on the right. If you want there to be pairs just make another card with a new color.