How do people with amnesia fully recover their memory?

I mean, do they just wake up one morning and remember everything, or do they remember things bit by bit, or as they see things that remind them of the memory?How do people with amnesia fully recover their memory?
It's usually a combination. It mainly depends on what causes the amnesia: traumatic event, a disease of sorts, head injury. If it's a head injury, minor, memories can come back all together. If it's the other two, they come back in fragments. Taking people to places they knew or enjoyed or have history can help most of the timeHow do people with amnesia fully recover their memory?
I believe that they remember things bit my bit... and or see things that remind them of their memory. Does a family or friend that you know that has amnesia?

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