Ecologists often study issues (____ the effects of human activities upon populations and ecosystems).issues(複數)(事物)-->關係代名詞which/ that +動詞 relate to
所以 which relate to= that relate to
which(S'= issues物) relate(v') to= that (S'= issues物) relate(v') to
a 選項錯在哪呢?----> whom relate to----> (1) who (S'= 人) relate(v') to
------> (2) whom + S' + relate to
20. Ecologists often study issues ____ t..-阿摩線上測驗