When using indirect or reported speech, the form changes. Usually indirect speech is introduced by the verb said, as in I said, Bill said, or they said. Using the verb say in this tense, indicates that something was said in the past. In these cases, the main verb in the reported sentence is put in the past.

What is the indirect speech of did not?

Direct speech: We have not separated. Reported speech: He clarified that they did not separate. Direct speech: We did not separate. Reported speech: He clarified that they had not separated.

Is did a past tense?

The past simple form, did, is the same throughout. The present participle is doing. The past participle is done. The present simple tense do and the past simple tense did can be used as an auxiliary verb.