Yes, it is true that -ing and un- have grammatical meaning.
Hope this helps! :)
I THINK ITS ACTIONS AND EVENTS
The correct option is C.
Get involve in a marathon race is a big deal and the very first step that one has to take is to go for medical check up and obtain approval from one's doctor to participate in the race. This is very important because of the exertions that the race involved.
He could be expecting someone or NOT expecting someone. Does he live in a dangerous society? Is he prepping himself to talk to sed person? I don't know much about poems or Edgar Allen Poe I just guess.
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