YOU SAID:
My favorite color is purple, light purple.
INTO JAPANESE
私の好きな色は紫、薄紫です。
BACK INTO ENGLISH
My favorite colors are purple and light purple.
INTO JAPANESE
私の好きな色は紫と薄紫です。
BACK INTO ENGLISH
My favorite colors are purple and light purple.
That didn't even make that much sense in English.