In the following question

Which security flaws does these protocols have?

Is the auxiliary verb "does" necessary? Would the sentence still be grammatically correct if I omitted it, in which case the sentence would read

Which security flaws these protocols have?


2 Answers 2


A beginning guide to questions like the one below:

Security protocols have flaws: Which security protocols do these protocols have?

Have is the declarative verb. All questions with have need the do or does as auxiliary:

Question: do, does x have. Very basic.

Does x have y? Do X's have y's?

You can't make a question in English with the verb have without the do or does. Do is plural and does is third person singular.

I have a car. Do you have a car? They have cars. Do they have cars? He has a car. Does he have a car?

All verbs in English (except the verb to be, where the subject and verb are inverted) require an auxiliary in the interrogative form.

He is rich. Inversion: Is he rich?

MORE ADVANCED: Please note: there are two ways to use the verb have in the present tense in English. They mean exactly the same thing. You can say:

  • Declarative: These security protocols have got flaws.

  • Interrogative: Have these security protocols got any flaws?
  • careful with the third person: Has this program got a flaw?

  • Declarative: These security protocols have flaws.

  • Interrogative: Do these security protocols have any flaws?
  • careful with the third person: Does this program have a flaw?

There is a lot more to be said about all this, but this is the basic idea about using have in the present tense in English in sentences where you basically have a subject + a predicate.

  • Not quite. You can't make a question in English without the verb have without the do or does except when the question word is the subject. Examples: "Who has (or who has got) the sauce?" "What English word has three doubled letters in a row?" Also, substantive "has" does not always need an auxiliary in the interrogative: "Have you [got] any milk?" is perfectly cromulent in the UK, and I thought it was grammatical, if unusual, in North America.
    – Colin Fine
    Commented Feb 27, 2018 at 23:21
  • @Colin Fine Someone who doesn't know the basics can't be expected to learn everything at once. The two ways to use the verb have in the present is very advanced. This is an ELL forum. Not ELU. Have/have got as present is a separate chapter. As is dropping the have as in: Have you any mil. Just saying. Sentences with who as subject are also separate lesson.
    – Lambie
    Commented Feb 28, 2018 at 1:11
  • correction: as in Have you any milk?
    – Lambie
    Commented Feb 28, 2018 at 1:18

To forego the auxiliary, you must begin the question with the verb, and convert it from a particular question (Which...?) to a yes/no question :

Have these protocols any security flaws?


Have these protocols specific security flaws?

In conversational register, however, most speakers would ask:

Do these protocols have any security flaws?

Do these protocols have specific security flaws?

  • In the UK, "Have these protocols got any security flaws?" is a normal conversational form.
    – Colin Fine
    Commented Feb 27, 2018 at 23:24
  • In the US as well, got brings it into conversational register.
    – TimR
    Commented Feb 27, 2018 at 23:56
  • This is an advanced usage. The OP didn't even know the basics or he would not have asked the question as he did. I think one should preach to the congregation and not to the choir. Got is not conversational in AmE. And that's an entire discussion. Also, ordinarily, one wouldn't say, in AmE or BrE: Have these products any security flaws? The got can be dropped in some circumstances but a regular speaker would not drop it in that type of technical utterance, on either side of the pond.
    – Lambie
    Commented Feb 28, 2018 at 1:16
  • @Lambie: I agree that this is a more advanced usage, but I disagree with you about got. Have you got any ideas? is a perfectly idiomatic conversational question in my dialect of AmE, which is spoken by around 30 million speakers, give or take a few million. And two security honchos could be talking to each other casually and one could ask the other Has that messaging protocol got any security flaws?
    – TimR
    Commented Feb 28, 2018 at 11:56
  • @Tᴚoɯɐuo [it's really a pain to have to copy and paste your name]. Anyway, where did I say in any manner whatsoever that "Have you got any ideas? is not AmE?? Where? I said there are TWO WAYS to say have in all varieties of English: have you got=do you have and I most definitely did not say anything at all about what you suggesting I said. I said that just "got" is not conversational per se. It is spoken rather than written, What is conversational is the dropping of the have, recently seen in: Got Milk?, the advertisement.
    – Lambie
    Commented Feb 28, 2018 at 15:52

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .