[Grammar] I can eat more than you can eat.

[kadioguy]

I can eat more than you can eat.
I can eat more than you can.
I can eat more than you can do.
I can eat more than you.

I can run faster than you can run.
I can run faster than you can.
I can run faster than you can do.
I can run faster than you.
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Are all of them acceptable? If not, could you tell me the reasons?

 

[kadioguy]

I am more beautiful than you are beautiful.
I am more beautiful than you are.
I am more beautiful than you.
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The first is not correct; the others are correct. Am I right?

 

[Matthew Wai]

I run faster than you do.

I think 'do' is an auxiliary verb rather than a full verb there.

 

[kadioguy]

We don't replace a verb with DO when it follows a modal.

But I see this:

do
auxiliary verb
used instead of repeating a verb that has already been used

'Will Kay come?' 'She may do.'

https://www.ldoceonline.com/dictionary/do
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In this sentence 'may' is a modal verb and 'do' is used to replace the verb 'come'. :shock:

 

[kadioguy]

But I see this:

'Will Kay come?' 'She may do.'

https://www.ldoceonline.com/dictionary/do
------------
In this sentence 'may' is a modal verb and 'do' is used to replace the verb 'come'. :shock:

So are there two modal verbs in this sentence ('may' and 'do')?
Is a contradiction between this sentence and what Piscean said (We don't replace a verb with DO when it follows a modal)?

Could you please help me?

 

[Tarheel]

That's not very natural. Try:

A: Will Kay come?
B: She might.

 

[GoesStation]

I think She may do is common in conversational British English.

 

[kadioguy]

DO is not a modal verb.

But we can see this:

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(Update)

OK, now I know that DO is an auxiliary verb, but that it is not a modal auxiliary verb.

(Question)
Is a contradiction between this sentence and what Piscean said (We don't replace a verb with DO when it follows a modal)?

 

[kadioguy]

Yes.

I should have qualified my statement more.

Could you tell me more, please?

I am confused. I don't know whether We can replace a verb with DO when it follows a modal. :-?

 

[kadioguy]

Could you tell me more, please?

I am confused. I don't know whether We can replace a verb with DO when it follows a modal. :-?

In conversational British English maybe 'do' can replace a verb although the verb follows a modal verb.

Am I right?


(Update)
The question is posted on https://goo.gl/XmkexV
(Why do I post the same question there? Because I don't get an answer.)