Ka pupuri ahau, I became (or shall become) holding.
Ka kore ahau e pupuri, I became (or shall become) not holding.
§ 40. Remarks on Tenses. The Present and Perfect may be also used either in Past time, or in Future time, when they respectively become either (a) Past Imperfect, and (b) Past Perfect, or (c) Future Imperfect, and (d) Future Perfect.
In the Future the addition of tera gives emphasis.
The Transitional denotes a transition or change from one state or action to another; or the commencement of a new action or condition, and may be either (e) Past or (f) Future: the actual time to be determined by the context.
Examples.
(a) Te taenga mai o Rewi e kokoti witi ana ahau, when Rewi arrived I was cutting wheat.
(b) Te taenga mai o Rewi, kahore ano ahau kia hopu i te hoiho, when Rewi arrived I had not yet caught the horse.
(c) Kia tae mai a Hori apopo e hopu ana ahau i te hoiho, when Hori arrives to-morrow I shall be catching the horse.