Primary Auxiliary Verbs (Do, Have, Be)

Primary auxiliaries

 Auxiliary verb 

Difinitions and Rules of Auxiliay verbs:

・Auxiliary verbs have Primary auxiliaries and Modal auxiliaries.

・Auxiliary verbs are verbs that are used to help main verb.

・Auxiliary verbs can not be used without a main verb.

 Primary auxiliaries 

Bedohave and their various forms are called primary auxiliaries.

 Primary auxiliary verbs are used together with a main verb to give grammatical information and therefore add extra meaning to a sentence, which is not given by the main verb.

・They are used to form the passive voice.

・They are used to form the continuous tense.

・They are used to form the perfect tense.


BeDo and Have are Primary auxiliary verbs, they are irregular verbs and can be used as main verbs

But Modal auxiliaries can never function as a main verbs.


Passive voice

The primary auxiliary verb be is used with a past participle to form the passive voice;

be(its various forms) + past participle=passive voice


RED=auxiliary   BLUE=past participle

・The money was taken.

・The door was opened.

・He was punished for lying.

Progressive aspect

The primary auxiliary verb be is used with a present participle to form the progressive aspect

be(its various forms) + present participle = progressive aspect


RED=auxiliary   BLUE=present participle

・I am writing.(present progressive)

・I have been writing.(present perfect progressive)

・I was writing.(past progressive)

・I had been writing.(past perfect progressive)


 It is the most neutral of all the auxiliaries.

  It has no individual meaning but serves as an operator for the formation of the interrogative and the negative of the present simple and past simple tenses and also foremphasis or to convey a coherent style.

 There is also a lexical verb "do" (= perform) which has the full range of forms including the present participle doing and the past participle done.

To form negative sentences when the verb is imperative, simple present or simple past. 

Do (Did,Does) + not + verb = Negative sentence


・I don't (do not) like cheese.

・I didn't (did not) see the movie.

・She doesn't (does not) watch TV.


In questions involving inversion where the verb is in the simple present or past tense.

There is no do-periphrasis in positive wh-questions beginning with the subject ( What happened?) And in yes-no questions where inversion is not necessary. ( He said that?)

do (did,does) + subject + verb=Question


Do you like coffee?

Did you see the movie?

・What kind of coffee do you like?

・Why don't you play with me?


The dummy auxiliary do is used for emphasis in positive statements.

In emphatic expressions where the verb is simple presentsimple past or imperative.

do (did,does)+ main verb=emphasis

・I do love you!

Do shut up!

・You did say that!

・You do look nice today!


・In short answers

 Example   Do you smoke? Yes, I do.

・Tag questions

 Example   You ate my cake, didn't you?


 Example   He speaks better than you do.

・To avoid repetition of a previous ordinary verb ( pro-form)

 Example   He asked me to leave, so I did so.


The formation of the perfective aspect by combining with past participles.

have (has,had) + past perticiple=perfect aspect


・He has eaten the cake.

・He had eaten the cake before he did homework .

・He will have eaten the cake tomorrow.