very harmful and able to cause illness or death =poisonous,剛好對比題目的harmless
marginal翻譯:小的, 微小的;少量的, 政治, (選舉中僅以微弱多數取勝的)邊緣選區( 或席位), ...
5 Some mushrooms are______, but most of ..-阿摩線上測驗