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suspicious; dubious; questionable; dodgy; shady; fishy
doubtful; unsure; uncertain; unlikely; implausible
untrustworthy; unreliable; clumsy; awkward; shaky; poor
strange; weird; eerie; spooky; uncanny
ominous (e.g. weather); threatening; dangerous (e.g. financial situation); uncertain
suspicious (of a potential amorous relation)
mysterious; bewitching; alluring; enticing; enchanting
怪しい人が家の前をうろついていた。
A suspicious person was wandering in front of the house.
昨夜、家の前をうろついていた人物は怪しかった。
The person lurking in front of the house last night was suspicious.
あの店は見た目ほど怪しくないですよ。
That shop isn't as shady as it looks.