every+ 基數(shù)詞+ 復(fù)數(shù)名詞=every+ 序數(shù)詞+ 單數(shù)名詞
作“每(多少)”解
如： every three days 每三天或每隔兩天
相當(dāng)于 every third day
"every other+單數(shù)名詞”
意思是“每隔一.”
如：every other day 每隔一天 every other tree 每隔一棵樹
every few+復(fù)數(shù)名詞”
意思是“每隔幾.”
如：every few days（每隔幾天）