Answer:
Internal can be you don't want bad things happening to your body, you don't want drugs affecting your health,etc.External could be you don't want it to affect your family or people around you.For example, like a cigarette if you are smoking in public you can be affecting others passing by or hanging out with you(external)but if it's just you by yourself smoking it is damaging your lungs(internal)
love is pain and pain is love. love hurts because sometimes if you show you care too much about that person youre judged and they back stab you but if you show no emotion you dont care about them. love could leave people scars in diffrent ways. wether its emotional scars or physical scars. or sometimes when you love a person you could lose them in a second or minute. sometimes when you love someone you would do anything for that person like stand in front of a bullet for them or get beat up by your parents or some strong people..or it could be sneaking out at night just to see them for a few minutes or seconds..and at the end they dont appreciate it which hurts. hope i answered your question.
Answer:
I believe it is cardiovascular since they all involve the heart
