What is the difference between somewhere and elsewhere.
My understanding is:
Somewhere-at a particular unknown place.
Elsewhere-at some place.
They seem identical.
"I was looking for Susan and went to her house. She wasn't there. She had gone somewhere." We don't know where.
"I was looking for Susan and went to her house. She wasn't there. She was elsewhere." Elsewhere is anywhere but her house
More often than "elsewhere" you will see "somewhere else", with the same meaning. "She wasn't there. She was somewhere else."