Can one use
a. Too many cookies are bad for you.
instead of
b. Having too many cookies is bad for you.
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Can one use
c. Many cookies are bad for you.
instead of
d. Having many cookies is bad for you.
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Can one use 'is' instead of 'are' in (a) and (c)?
One meaning of (c) is: There are many cookies that are bad for you. (Some aren't bad, but many are.)
I am not sure that (c) can be used instead of (d) though.
Many thanks.