Hi
Please see below:
1- He is legally blind. ( Does it mean he is totally blind?)
2- She was clinically dead.(What does it mean?)
Tom
Hi Tom
Despite the risk of possibly giving a morally questionable answer here:
Legally blind could be totally blind or almost totally blind (i.e., vision is severely impaired).
Clinically dead --> I understand this to mean that both breathing and pulse have stopped.
Amy
Amy, could you please shed some light on it? What do you mean by saying so?
Tom
Hi Tom
In this day and age, it’s possible to keep people alive with machines. A hundred years ago such people would have simply died.
Some people feel it’s morally wrong to allow “clinically dead” people to die. They feel that not keeping the people alive with machines — even when all/most doctors agree that the person can not survive without them — is morally wrong.
Amy
He doesn’t have to be completely blind, but he is blind enough that for all legal purposes he is considered blind. I worked with a lady who was legally blind, so, for example, she was forbidden to drive, etc. However, she was not completely blind, because wearing a pair of Coke bottle glasses and using a big magnifying glass, she made her living as a proofreader.
This is the same as saying the person is “brain dead”. Her body is still functioning, and it’s possible to keep her body alive with machines, but her brain is not working, and she will die if you turn the machines off.
Dear Amy and Jammie
My concept is 200% clear now. So, 2000 thanks for the generous help! 
Amy, as you and Alan advised me “many threads ago” that “cannot” can be used as two words for the sake of emphasis…I saw it today. And, if I am not mistaken, you did it on purpose.
Thanks again
Tom
Amy, if memory serves me correctly, there was a feature in the Reader’s Digest in which the author wrote:
…keeping the child alive on machine…
Could you please tell me if both prepositions are correct with no change in meaning?
Yours
Tom
No, Tom, actually I didn’t intentionally separate the word. Either that was a typo or my subconscious decided to emphasize. :lol:
Amy
Hi Tom
In the context, there really isn’t much difference, but I’d describe it this way:
“with machines” → by using machines
“on machines” → connected to machines
Amy