Sentences without the comma with 'therefore'

[Tung Quoc]

Dear teachers,

Please read:

1.Tom didn’t study. Therefore he failed the test.
2.Tom didn’t study. He therefore failed the test.
3.Tom didn’t study. He failed the test therefore.
4.Tom didn’t study; therefore he failed the test.
5.Tom didn’t study; he therefore failed the test.
6.Tom didn’t study; he failed the test therefore.

All are correct?I think all are correct without the comma with "therefore". Is it right?

Quoc

[Torsten]

[Mister Micawber]

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I don't think much of #1-#3. I think the ideas are too closely related to be separate sentences.
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Native English teacher at Mister Micawber's

[Tung Quoc]

Dear Sir,

You mean all my 6 sentences are correct in grammar but you don't like the sentences (1) and (3).


Quoc

[Mister Micawber]

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No, I mean I don't like #1 through #3 (i.e. including #2). Linking adjuncts are best united more closely to their referent by a semicolon-- that is my feeling. Separate sentences should be reserved for special stress:

We don't like your hairstyle, we don't like your attitude, and we don't like your coming in late and leaving early every day. Therefore, you are fired.
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Native English teacher at Mister Micawber's

[Tung Quoc]

Dear Sir,

Please read:

We don't like your hairstyle, we don't like your attitude, and we don't like your coming in late and leaving early every day. Therefore, you are fired[/i].

Can I write as follows:

a. We....day. Therefore you are fired.
b. We....day. You are fired therefore.
c. We....day. You are therefore fired.

Quoc