§ 63. Whom, or which. When the relative in English is objective, and is governed by a verb or by one of these prepositions: by, by-means-of, on-account-of, by-reason-of; the verb in the relative clause is followed by nei, na, ra, or ai, without a preposition; and in the present tense ana after the verb is omitted. For the force of nei, na, and ra, see [§ 18]. Use ai only with the past and future. The subject of the verb in the relative clause may either be expressed directly, or it may be implied in a possessive definitive placed before the antecedent.
Examples.
Te whare e hanga nei koe, the house which you are building.
Tau pukapuka e korero na, that book which you are reading.
Te mea e raru ai ahau, the thing by means of which I shall be perplexed.
Tau tangata i karanga ai, the man whom you called.
§ 64. Inverted Construction. In those cases in which the relative is governed by the verb in the relative clause the construction may be inverted, by making the verb passive ([§ 47]), with the relative as its subject.
Examples.
Te whare e hangaa nei e koe, the house which is being built by you.
Te pukapuka e korerotia na e koe, the book which is being read by you.