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1. All I need are cigarettes.

2. All I need is cigarettes.

3. All I need are a cigarette.

4. All I need is a cigarette.

Which of the above sentences is acceptable?
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1. All I need are cigarettes.

2. All I need is cigarettes.-- Seems odd, but in use; the speaker is envisioning a package (similar to ordering 'a coffee')

4. All I need is a cigarette.
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Mister Micawber.

2. All I need is cigarettes.-- Seems odd, but in use; the speaker is envisioning a package (similar to ordering 'a coffee')

I see nothing odd in all is when all means everything: All is well that ends well. There is a relative clause in the above sentence and all is the subject of is:

All [that] I need is cigarettes.

Cigarettes isn't the subject of the main clause and thus are is odd to my ear. Of course the plural must be used when all means everybody: All are present.

CB
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Comments  
Number 4 is the most acceptable

All I need is a cigarette
Students: We have free audio pronunciation exercises.
All I need is a cigarette because it can identify your specific or general need.