英文Grammer問題 (20點)

1) Should / Ought to / Must / Have to
都可用來表達說話者的期望，分別在於強烈程度。

Should (應該) 溫和的建議：
You don't look so well. You should perhaps see a doctor.
You shouldn't stay too late in the office. It's not so safe in the neighborhood.
Should I give you a cup of coffee?

Ought to (理應) 比 Should 稍強的提醒：
You ought to submit the report before 12:00pm, so please hurry!
You ought not let your son smoke. He's only 12! (ought not 後不用 to)
Ought to 並無 question form，可用 Should 代替。

Must = Have to (必須) 強烈的要求：
You must (have to) work hard if you want to pass the exam.
You mustn't take drugs!
Must I finish the work today?

Must 是 simple present，若需用於其他 tenses，可用 have to 代替。
Must not (切勿) ≠ Don't have to (無須)

2) Reported Speech
必定是句子，不可是問句。就算是在複述問題，其形式都必須是句子。

John asked, "Mary, when is your birthday?"
John asked Mary when her birthday was.

When is your birthday 是問句，於 Reported Speech 中須變成句子形式 when her birthday was.

Peter asked, "Where can I buy the ticket?"
Peter wanted to know where he could buy the ticket.

若原問句沒有 object，Peter asked 應變成 Peter wanted to know.

Molly asked, "Do you love me?"
Molly asked me if / whether I loved her.

上述原問句看似無 object，但問題是 Do you...，可見 object 就是我。
若原問句屬 close-ended questions (yes / no questions)，Reported Speech 須用 if / whether (是否...)。

3) Conditional Sentences

形式取決於說話者認為 if clause 的假設會發生的可能性有多大。

First Conditional：
If you keep on lying to everybody, you'll have no friend left very soon!

If clause 的假設會發生的可能性很大
If clause：Simple Present
Main Clause：Simple Future

Second Conditional：
If you won the lottery tomorrow, would you share the money with me?

If clause 的假設會發生的可能性很微

If clause：Simple Past
Main Clause：Would / Could / Might + bare infinitive


Third Conditional：
If you had killed him yesterday, you would have gone to jail today!

If clause 的假設根本毫不可能 (從未發生)


If clause：Past Perfect
Main Clause：Would / Could / Might + Have + Past Participle