While I was writing a textbook I gave an exercise for students. Since the exercise was difficult, I gave an example and gave the instruction
One (example) is done for you
The editor corrected it as
One has been done for you
I would like to know whether my instruction “one is done for you”
is wrong or not.
I have referred to many textbooks and found both constructions. Later, I consulted a famous linguist who told me that both are correct but had a difference in meaning. The linguist was Rod Mitchel whom I consulted on LinkedIn. He gave an elaborate explanation which I now forget and the link is broken. I can remember only vaguely.
The first one means the example is ready for you. You can have a look at it if you like.
The second one means I have taken care to give an example for you and you can do the exercise with its help.
I hope you would be kind enough to answer my question
As sentences, both are perfectly grammatical. In the context of pre-completed exercises in a textbook, though, “has been done/completed” would be more common, stressing the perfective aspect of the action, so I would agree with your editor here.
Credit: Janus Bahs Jacquet
As Janus says, both are grammatical. The difference in meaning is negligible for just about anyone not writing a treatise on English grammar (focus totally on the completed example (‘is’) vs focus rather more on the anonymous agent). I’d expect to see ‘… one is done for you’ in the formal, erudite, rather stuffy old textbooks that I was exposed to 55 years ago and the more natural-sounding ‘one has been done for you’ in modern treatments: this is really just a style issue for the vast majority of people.
Credit: Edwin Ashworth