You are the last person I'd want/ want & She never has had or has never had.

[Alexandro]

Hi everyone,

I heard some sentences on television. I should like to have your advice, please. Here they are:

- You are the last person I'd want Krystina to be with when I'm away.
- You are the last person I want Krystina to be with when I'm away.

Do both sentences have the same meaning or is there a significant difference in meaning? If there's not a significant difference in meaning, then, please, explain too.

The other sentences I have a question about is the following:

- My cousin never has had any taste. (it was said in a rather sarcastic way and also with a tiny bit of animosity).
- My cousin has never had any taste.

In my opinion both are correct, but one should change the intonation in the first one to make abolutely clear that the cousin never has had any taste.
Some grammars over here explain that an adverb should almost always be placed after the auxiliary or after the first auxiliary as in: 'I should never have allowed him to do that.' rather than 'I never should have allowed him to do that.' I think these last sentences make sense too, but please your advice is very welcome as always.

Thanks
Alexandro
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'Everyone can mistakes! After all, nobody's perfect.'

[Beeesneees]

No significant difference in the meaning in practical terms. 'I would want' is more hypothetical/conditional. 'One of the uses of 'would' as a modal verb is to say what you want (or in this case, don't want) to happen.
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"Inside every old person is a young person wondering what happened."
Terry Pratchett

[Alexandro]

Thanks BN,

But could you, please, read my post again, because while you were replying, I was making a few alterations.

Thanks
Lex.
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'Everyone can mistakes! After all, nobody's perfect.'

[Beeesneees]

I don't see any difference in what I read earlier to what is there now. I don't have anything to say about the last part. You have already correctly indicated that all the sentences can be correct in various contexts.
_________________
"Inside every old person is a young person wondering what happened."
Terry Pratchett