The auxiliary verb DO is required to form questions with all verbs except BE and modal verbs. Here are some examples with Yes / No questions. Remember, it is impossible to ask these questions without the auxiliary verb DO.
The same rule applies to Wh– questions.
Note: It is possible to form questions with the verb HAVE without using DO, but this form is increasingly rare. American English speakers prefer using DO.
|Do||you||have||a pen?||Have you a pen?|
|Does||he||have||a new idea?||Has he a new idea?|
Here are examples of correct questions on the left and incorrect questions asked by students who do not know the grammar rules.
|Correct||Incorrect||Reason for error|
|Do you speak English?||use of BE instead of DO|
|Does this train go to Chicago?|
|Do you have change for a euro?||use of HAVE instead of DO|
|Does the room have a bathroom?|
|What time does the bank open?||absence of DO when main verb is not BE|
|Where do you live?|