Quote Originally Posted by Боб Уайтман View Post
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I understand that I need "of" in the phrase like "in the shade of green trees" (в тени зелёных деревьев), since it is genitive in the Russian phrase (деревьев).
But why shouldn't I use the "of" in the phrase like "five tall green trees" (пять высоких зелёных деревьев)? It is the same genitive there! Don't I need "of" in English?

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...have to say "a lot OF cars" but "many cars" without "of". The same way as I remember I have to say "hundreds OF cars" but "one hundred cars". It does not seem logical to me, but I've got used to it nonetheless.
Боб, you're so good at all this that you probably know about the additional formations:

"one hundred of the cars" so when it is a sub-quantity, it is genitive, with 'of'. "Many of the cars were old."

"five tall green trees" => "five of the tall green trees" a sub-quantity. So there is a specificity thing happening.

It depends on what the emphasis is on.

"Take five men and search the field." vs "Take five of the men and search the field."