Shared。My Life。

＊規則動詞的過去式，是在動詞字尾加 -ed。而不規則動詞的過去式則不是以 -ed 結尾。
EX: I work in a travel agency now. Before that I worked in a department store.
      We invited them to our party, but they decided not to come.

write -> wrote / see -> saw
go -> went      / cost -> cost

EX: Mozart wrote more than 600 pieces of music.
      I went to the movies three times last week.



＊過去簡單式的疑問句及否定句，必須使用助動詞 did/didn't + 動詞原型(EX: enjoy/see/go 等)
EX: Did you go out last night?
      Yes, I went to the movies, but I didn't enjoy the film much. 
EX: Did you have time to write the letter? No, I didn't.
EX: I didn't do anything.
// 若 do 意思為「做」，則為該句的主要動詞，仍必須使用助動詞 did。



＊be 動詞(am/is/are)的過去式形態為was/were。句中動詞為be動詞時，不需使用助動詞did來形成疑問句及否定句。
EX: I was angry because they were late.
      Was the weather good when you were on vacation?
      They weren't able to come because they were so busy.

[ 節錄自 Grammar is Use Intermediate - Unit 5 ]