The cat was a beautiful animal, of unusually large size, and entirely black. I named the cat Pluto, and it was the pet I liked best. I alone fed it, and it followed me all around the house. It was even with difficulty that I stopped it from following me through the streets.
밑줄친 with difficulty 는 부사로 봐야죠?

맨투맨에 보면 with + 추상명사 = 부사 라고 하던데 그럼위 표현이 부사라면

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