反義詞是formerly，例如：
1、I learnt that the house had formerly been an inn.我得知這座房子以前是家客棧。
2、This fact has led naturalists to believe that the Isthmus was formerly open.使許多自然學者相信這個地蛺在以前原是開通的
3、Many products formerly made of metal now are made of plastic.以前用金屬製造的許多產品現在都用所料製造了。
ago，beforetime，formerly，previouslybefore 英[bɪˈfɔ:(r)] 美[bɪˈfɔr，-ˈfor] prep. 在…之前 先於，優於 當着…的面 與其… conj. 在…之前 在…以前 比…早些 與其… adv. 先前，從前 在前，在前方 [例句]Annie was born a few weeks before Christmas安妮出生在聖誕節前幾周。
