Hi litebrite. "Machucar" is the act of hurt someone, like "I'll hurt you with this knife" or "Eu vou machucar você com esta faca". "Dói" means "pain", it's all about "feeling". "Magoar" is like "hurt" but emotionally, like "You hurt me when you swear to me" or "Você me magoa quando me xinga". Is it clear? Following some corrections on your questions: "Qual a diferença..."; "Todos significam a mesma coisa"; "Por favor, corrijam meus erros gramaticais".

First at all in Portugal it's really rare someone saying "Machucar". Machucar = http://www.priberam.pt/dlpo/machucar Dói = http://www.priberam.pt/dlpo/d%C3%B3i Magoar = http://www.priberam.pt/dlpo/magoar "Dói" it's like It hurts "Magoar" Hurts. For example: I got an accident and I got hurted = Tive um acidente e magoei-me I crash my knee and I got a pain or I crash my knee and I've pain = Aleijei-me / Magoei-me no joelho e dói-me.

In Portugal, they may use these verbs differently. In Brazilian Portuguese though, we have: MACHUCAR: the act of hurting, mainly in a physical manner, but also metaphorically. It demands a direct object. "Ben hurt his sister with that action figure over there" = "O Ben machucou a irmã com aquele boneco ali." "That girl hurt me with those words" = "Aquela garota me machucou com aquelas palavras." DOER: Feeling pain, used with parts of the body. It can be used metaphorically too. It doesn't need an object (intransitive verb). "My leg hurts" = "Minha perna dói." "My soul hurts" = "Minha alma dói" MAGOAR: to hurt metaphorically only "Her attitude hurts me" = "A atitude dela me magoa." "Sometimes it lasts in love, but sometimes it hurts instead." ="Às vezes permanece com amor, às vezes, em vez disso, magoa."