Part B: The Verb

6. Perfective Mode
In English most of our verbs can be changed from the present to the past tense by adding a suffix 'ed

‘I work' becomes 'I worked'

'I stay’ becomes 'I stayed'

In Denes¶øiné, a similar change can be made in the verbs, so that words with imperfective meaning may acquire perfective meaning. As imperfective means the action or condition is still taking place, perfective means that the action has been completed, and is no longer taking place.
The perfective is indicated in two ways:

1. The addition of a prefix.
2. The addition of a prefix and an alteration in the form of the stem.

The choice of the perfective prefix is not easily predicted, and there is no basis for predicting the stem. Therefore most perfective forms must be learned as new words.