You think everyone of voting age in this country has or can afford to own a car?
I read the above sentence at
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Could you please explain the use and meaning of the preposition "of" in "everyone of voting age..."?
Why can't we use from in that phrase?

In that sentence, "voting age" is understood to mean any age 18 and above. It would also be possible to say "everyone above voting age" or perhaps "everyone from voting age upwards", in which case "voting age" would be interpreted as meaning age 18.

JigneshbharatiWhy can't we use from in that phrase?

"Why can't we use 'from' in that phrase?"

Because it would be unidiomatic and meaningless. To be of voting age is to be within the age range from the first age you can vote to 120 or so, the record for human logevity. "Of" has a thousand uses.

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