"I do not have enough money to buy a car (with)."
My grammar book says that 'with' is omitted to modify the 'money'. Do you agree that we should think of the presence of prepositions when 'to infinitive' modifies 'nouns' behind? Thank you so much as always and have a good day.
***** NOT A TEACHER *****
I was dithering about how to respond, but then I remembered a piece of advice I happened upon while reading Grammar Girl Presents the Ultimate Writing Guide for Students: When you can leave off the preposition and it won't change the meaning, leave it off.
If you insist on using 'with', you could say 'I do not have enough money with which to buy a car'. Here 'with' can't be omitted.