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fly (any insect of infraorder Muscomorpha)
person of no worth; pisher; scrub
部屋に蠅が飛んでいます。
There is a fly flying in the room.
蠅がうるさくて眠れません。
The flies are noisy and I can't sleep.
窓を開けたら蠅が入ってきました。
When I opened the window, flies came in.