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strange; odd; peculiar; weird; curious; eccentric; funny; suspicious; fishy
unexpected
change
incident; disturbance; disaster; accident; emergency
flat
彼の行動は少し変だ。
His behavior is a little strange.
外から変な音が聞こえますか。
Do you hear a strange sound?
そんな変なことを言わないで。
Don't say strange things.