(與動詞be，seem，appear 連用時，代替句中的主語)(used to introduce a clause or sentence)：T～is a letter for you. 有你一封信。T～are several different kinds of pepper. 胡椒有幾種不同種類。T～don't seem to be any mistakes in this. 這個似乎沒有什么錯。T～appeared to be nobody in the classroom. 看來教室里沒有人。T～were staff meetings and a press conference daily. 每天都舉行全體員工會和記者招待會。T～was (or were) a horse and a cow in the pasture. 牧場上有一匹馬和一頭牛。T～was (or were) a glass，two plates，and a teapot on the shelf. 架子上有一個杯子，兩個盤子和一把茶壺。