Distinguishing between good and evil is difficult, even for adults.
After hitting one year old, she started understanding what is right and what is wrong.
He's just a baby, so he still doesn’t know the difference between right and wrong.
You have morally good and bad. This is the battle between good and evil.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.