✔ 最佳答案
derek32161：
首先我看到你這兩句句子, 直覺上感到你的英文基礎不錯, 只需畧為指點,就應會芧塞頓開了：
你的第一句" This man was killed two days ago. "已在文句結構和文法上也很清楚正確而通順地表達了你的意思 " 這個男人兩日前被殺."了。
你要加强表達則可以用" This man has been killed two days ago." 雖然句子在結構和文法也全對但欠缺必要,但在某塲合上就必要用以達到加强表達的作用。例句如" I believe this man has been killed two days ago " 就句子不會用了現在完成式的動詞 has been killed而覺得不妥當了,而在這句子中" this man has been killed two days ago" 是變成了文法上一個adverb clause來形容believe這個現在式動詞的,所以這個助動詞句子亦必要用現在完成式(present perfect tense)" has been killed..."了。
但第三句" This man had been killed two days ago." 單句寫出來就有問題了, 因你沒有原因地用了過去完成式的文法也, 但假如有原因或原因,則要同時寫出來如 " This man had been killed two days ago before his body was found." 就對了。我相信你亦應明白了 ; 因為 " his body was found"是過去式
而在過去式之前他已被殺, 所以用過去完成式動詞" This man had been killed "加在過去式動詞之前就對了。
道理很簡單,被殺是發生在屍體被發現之前,既然屍體被發現was found是過去的動詞(past tense),那被殺的事發生得比was found 還早,所以被殺的動詞便要用過去完成式(past perfect tense) had been killed 了。
例句其實你明白了原則你亦可隨手寫得百數十句, 我且舉例如下：
John was given two hundred dollars by his mother this morning.
John had been given two hundred dollars by his mother this mornibg before she went to work.
Mary was kissed by John yesterday.
Mary had been kissed by John yeaterday before she showed her consent.
希望能畧畧幫到你。
