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dark; gloomy; murky
depressed; dispirited; down in the dumps; dark (mood)
dark (in colour); dull
ill-boding; dark (e.g. past); suspicious
unlikely (to succeed); hopeless; unpromising
unfamiliar (with); ignorant (of)
この部屋はちょっと暗い。
This room is a bit dark.
暗くなる前に帰ったほうがいい。
You should go home before it gets dark.
暗い道を一人で歩くのはやっぱり怖いなあ。
Walking down a dark road alone is scary after all.