Did

                                                           Did

It is used to separate an action that took place in the past.

                             I

                             we

                             you

                             they         -------------- Did + base form

                             she

                             he 

                             it

NOTE 1:

it is denotes the completed actions before the pastense verb is used.

                            We learn t the lesson.

                             I understood the story.

                             She asked a question..

                             They bought a car

                             It worked well.

NOTE 2:

To emphasize the past actions we used the helping verb did along with baseform verb.

                             Ramu did work well.

                             I did the shopping last night.

                             He did give a speech.

                            You did help me.

                             I did get a job.

                             He did go there.

NOTE3:

To express the negitive sentences we add "not" to the helping verb.

                             I did not practice well

                            You did not answer my question.

                            They did not solve  the problems.

                            She did not write the exam.

                             I did not work properly.

                             They did not decorate room well.

NOTE 4:

To express the intergative sentences we starts with the helping verb.

                            Did you give  a speech?.

                           Why did you help her?.

                            How did they travel?

                            What did you do yesterday?

                            Whose help did you take?

                            When did you listen this song?

                            Where did you buy this shirt?

NOTE 5:

Negitive intergative sentences are expressed as follows.

                            Did not you finish your work?

                            Did not you meditate today?

                            Did not she motivate the customer to buy this policy?

                            Did not you rule the people?

                            Did not they fabricate well?