The hif’il infinitive construct has the ה prefix seen in the perfect, with the vowel pattern of the imperfect. Thus, in most roots the vowel under the prefixed ה is a patakh: הַזְכִּיר; in empty ע roots it is kamatz: הָקִים; in פ”י roots, the י root letter becomes a וֹ vowel letter, and the resulting infinitive construct is identical to the perfect: הוֹלִיד.