“to have enough money or time to be able to buy or to do
Why is it used with “can“? Why don’t people simply say “I don’t afford it” instead of “I can’t afford it“?
As you can see, “being able to” is hidden in the meaning of “afford”. So it seems redundant to me to use it with “can”.
To me, “I cannot afford this car” means “I am not able to have enough money to be able to buy this car“. But “I don’t afford this car” makes more sense to me since it means “I do not have enough money to be able to buy this car“.
The meaning of afford we are considering here is that which the OED gives as its fifth definition: ‘To manage to give; to spare (time, room, money, etc.)’.
That, by its nature, is not something we do or don’t do. It’s something we are able or unable to do. When we try to substitute spare for afford, we encounter the same problem. We don’t say of something expensive *‘I don’t spare money for it’ any more than we say *’I don’t afford it’.