Are these correct? A lof the, plenty of the?

a lot of the evidence was lost.
plenty of the evidence was lost,
a lot of the film was worth watching,
plenty of the film was worth watching,

plenty of the workers are eager,
a lot of the workers are eager,

None of the evidence was lost.
none of the film was worth watching,
Is there something wrong with these usages?
thanks alot…

All your sentences seem grammatically correct to me. However, I wouldn’t say ‘plenty of the film was worth watching’. It sounds a bit awkward somehow. I prefer ‘a great part of the film’. But this is only my personal opinion and preference.

I agree with Conchita they seem rather awkward.Moreover you should know norms od usage these combinations.I may help if you like!

I would realy be grateful to you if you might help me…
I really need your help…

As you know "a lot of"and “plenty of” are used both with countable and uncountable nouns.But there is a tendency to use "plenty of "mainly with uncountable nouns. It’s often used in informal speech also.

I agree. Using “plenty of” sounds awkward. This is especially true when the phrase is used at the beginning of the sentence. I think it will sound better if it is used at the end of the sentence.

what about the ‘‘the’’ in plenty of the, alot of the,lots of the.Is ıt correct if we use the with them?

Yes, mrdmrd, it is correct to use the article ‘the’ with these phrases whenever you refer to a specific noun or in place of the demonstratives (this, that, these, those).