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A. The computer does not work. (simple present)

B. The computer is not working. (present progressive)

1. What's the difference in meaning between these sentences?
2. Does it have something to do with the permanence of computer's working condition?

C. Top-notcher is one whose test result gets the highest score. (simple present)

D. Top-notcher is one whose test result got the highest score. (simple past)

E. Top-notcher is one whose test result has got the higest score. (present perfect)

3. Which sentences above are reasonable?
4. What's the difference in meaning between/among the answers in #3?

I would very much appreciate your assistance.
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These are the typical situations that come to mind:

A. The computer does not work. (simple present) It hasn't worked for some time, maybe for months. Maybe it has to be taken to a shop to be repaired. Maybe it's standing in a corner gathering dust or packed in a box to take it in for repairs.

B. The computer is not working. (present progressive) At the very moment I am speaking, it's acting up (causing trouble), or it has been acting up for the last few hours. Maybe the problem will correct itself if I make some small adjustment, or restart it, or just wait.

That said, the two can be interchanged because the speaker's attitude about the situation in also encoded in his choice of tense. Emotion: sad

In A the speaker suggests total and/or permanent inaction; in B the speaker suggests sporadic and/or temporary inaction.

C. A top-notcher is one whose test result gets the highest score. (simple present)

D. A top-notcher is one whose test result got the highest score. (simple past)

E. A top-notcher is one whose test result has got the higest score. (present perfect)

They are all reasonable, but D mixes tenses (is, got), so it isn't as good. They all mean about the same thing. Since it's a definition of a term, C is best in my opinion.

CJ
Comments  
CJ,

Thank you so much for your explanation. It was so kind of you.
It covered everything I needed to know. Cheers. Emotion: smile