Usage of ‘I have doubt that’

The problem with first sentence is its use of the word "why." The sentence would read more intelligibly:

"Some people may have doubts that investing ..."

However, the thought would be conveyed more effectively:

"Some people doubt that investing ..."

If required to use the noun form of the phrase in question, I would use a stronger verb than "have:"

"Some people harbor doubts that ..."
That is to say, some hold guarded or barely expressed doubts.

Hi Will, thanks for your points and your suggestion. I will surely take note.

You mentioned that the problem is the word "why", but is this sentence considerably correct? no doubt that it may sound a bit weird, but I would like to know is this sentence grammatically correct? is it acceptable? is it publishable?

"Some people may have doubt that why invest in these sectors during the economy slump?"

I have few examples using DOUBT with THAT:

(1.)What if scholars can prove beyond reasonable DOUBT THAT the Koran was not dictated by the Archangel Gabriel to the Prophet Mohammad during the 7th century
(2.) Perle: ‘I Have Very Little DOUBT THAT Bush Would Order ‘Necessary Military Action’ Against Iran.’
(3.)  I have no DOUBT THAT....

Compare with this sentence:
"Some people may have DOUBT THAT why invest in these sectors during the economy slump?"

Is it Grammatically ACCEPTABLE????

Alternatively, I can use:
(1.) He has DOUBT ABOUT…..
(2.) I have no DOUBT ABOUT
(3.) I have no DOUBT IN

Nomad your third post indicates a deft understanding of the phrase "doubt that."

However, the example sentence of your initial post ("Some people doubt that why ...") is not just weird, it is defective at the level of syntax rather grammar.

On that point, consider this simple modification:

Some doubt that. Why invest in these sectors during an economic slump?

The two sentences are correct in every respect, but when run together, as in the example, a problem arises. Why?

The terms, "that," a demonstrative term, a term that points something out, and "why," an interrogative term, a term that questions, logically cannot be combined without some intervening term--such is the clash between their functions.

Thanks Will !!!

Last test:

"Some people may have doubts in investing into these sectors during the economy slump."

Is the above statement perfect CORRECT?

Thanks.

The original phrase in question: "Some people may have doubt that why invest in these sectors during the economy slump?" is a non-sequitor. The problem is that "Some people may have doubt that..." must be followed by an assertion that can be viewed as either true or false.

Something like: "Some people may have doubt that investing in these sectors is prudent during the economy slump." is ok because "investing in these sectors is prudent during the economy slump" is an assertion that is either true or false. Either it is a good idea or a bad idea to invest now. If the economy is bad, then you can doubt an assertion that it's a good time to invest.

But, "why invest in these sectors during the economy slump?" doesn't assert anything. You can't doubt a question. It's like saying "I doubt that who is at the door?" You can say that "I doubt that John is at the door" or you can say that you doubt that anyone is at the door, but you can't say that you doubt that who is at the door.

In order for something to be doubtable, it has to assert something to be doubted in the first place.

Oh, and instead of "Some people may have doubts in investing into these sectors during the economy slump." I would suggest "Some people may have doubts about investing in these sectors during the economy slump."

"Some doubt that. Why invest in these sectors during a slumping economy, they ask?"

That construction would have obviated Porche's objection to an example I used in explaining that the terms "that" and "why" cannot be combine as immediately adjacent terms of a single sentence.

Adding that attributive phrase "they said," the relationship of the two sentences would have been made explicit.

I would say that "Some people may have doubts in investing into these sectors during the economy slump." is absolutely fine, except that I would perhaps use 'about investing' instead of 'in investing' to avoid the double in in which sounds strange when you say it.

In addition to the previous comments and suggestions, the statement would read better if "may" were replaced with might.

Refer to Will's comment below:
"The terms, "that," a demonstrative term, a term that points something out, and "why," an interrogative term, a term that questions, logically cannot be combined without some intervening term--such is the clash between their functions."

About the usage of combining the DEMONSTRATIVE and INTERROGATIVE terms, are the following statements grammatically correct? and Why?

1.) I am still not clear WHAT I need to do in this case.
2.) I am still not clear THAT WHAT I need to do in this case.

Any input?

Nomad, both are incorrect, but 2.) is more incorrect than 1.)

1.) is incorrect because the adjective "clear" cannot be followed by any noun phrase (NP), irrespective of whether the NP is a noun, a pronoun, or a what-clause (not the interrogative "what"), which is always a NP, as in 1.)

However, if you insert the preposition "about" just after "clear," then 1.) would be correct. In that case, the what-clause would be the object of the preposition "about."

2.) is both syntactically and semantically incorrect. The addition of the conjunction "that" just compounds the syntactic error.
2.) is semantically incorrect because it makes no sense. The conjunction "that" (It's not a demonstrative pronoun or noun here, or where previously cited by Potomac Will) sets up a clause whose subject is the what-clause "what I need to do in this case." Thus, we have a subject without a predicate. That's the syntactic error that causes the sentence to be nonsensical.
The brain expects a predicate to follow the what-clause. For example, "I am still not clear that what I need to do in this case is wake up."

By the way, in linguistics, syntax, semantics, and phonology are the three main subsets of the grammar of any given language. Thus, if something is syntactic, then it's also grammatical.

Semantics is the study of the meaning of words, phrases, sentences, and paragraphs. Nearly everybody I've heard misuses the word "semantics," much to the detriment of meaning and truth. Semantics is not hairsplitting. It's the most important and consequential of the three and underlies the other two.

Clarifying "that"

1.) As a demonstrative adjective: "She loves that cat."

2.) As a demonstrative pronoun: "That was not what I meant at all, not at all." -- T. S. Eliot

3.) As a subordinating conjunction: "He knew that he was wrong."
In this case, "that" joins the preceding independent clause with the following subordinate clause.

Nomad, Laura, #1 could also be corrected to the simpler "IT is not clear what I need to do"

'"Nomad, Laura, #1 could also be corrected to the simpler "IT is not clear what I need to do"'

I agree, Anon. This is a very good solution for 1.), and it's syntactically correct.

However, that's not apparent from the standpoint of traditional grammar as I learned it in 8th grade. The problem is that "clear" is followed by a noun phrase (NP), which is a what-clause in this case. You have to resort to transformational grammar to demonstrate the correctness of this sentence.

The deep structure is the meaning. The brain, without need of any conscious deliberation, automatically applies a succession of syntactic rules, each resulting in an altered structure, until the surface structure is reached.

The structure immediately under the surface structure is:
"What I need to do is not clear." The what-clause is the subject of the predicate "is not clear." Now the last syntactic rule is applied. This rule allows you to substitute "it" for the entire what-clause and move the latter to follow the predicate of the outer clause, "is not clear."

Thanks to transformational grammar and its discoverer, Noam Chomsky, your sentence can be shown to be syntactically correct.

Clarification of rule banning a NP (noun phrase) from following "clear."

In the original sentence -- "I am still not clear WHAT I need to do in this case" -- clear is a predicate adjective, not an attributive adjective. Of course a NP can follow the latter, as in, "She has no clear idea about her plans." However, when any adjective is a predicate adjective, a NP may not immediately follow it prior to the application of the rule I cited above, which allows the substitution of "it" for the what-clause and the displacement of the what-clause to the position immediately following the predicate adjective.

Is it correct if I write: We have to share doubts, suggestions, and activities related to the course.
or

the terms: "clear doubts" or "i have a doubt", are they acceptable?

please i need an aswer asap!!!

One can say "I doubt ......." or "I have doubts...................".
I do not think that "I have doubt..........." is correct.

@princess14 ... I think that "We have to share doubts, suggestions, and activities related to the course." is ok. It's out of context so I don't know if "need" is better than "have to". But as written, it is ok.

What is "clear doubts"? That's sounds oxymoronic ... If it is clear, then how can it be in doubt?

You can say "without a doubt" or "without any doubts" but the gainsay is "with doubts" or "I have doubts".

Perfect Pedant, "doubt" as a noun can be either uncountable or countable. If one can have much doubt or some doubt, or little doubt, then one can have doubt. "I have doubt" is fine.

@porsche
"I have doubt" may be grammatically correct but it does sound strange. Normal usage would be "I have doubts" or "I have my doubts".