It is natural to assume that in the system of verbal categories there is some hierarchy, that is, some categories are above others, determining their possibilities. To give a clear example: the category of voice to some extent dominates that of aspect, as there are fewer continuous forms in the passive than in the active voice: such continuous forms as shall be writing, have been writing, had been writing find no counterpart in the passive. We could also say that the passive voice limits the possibilities of the continuous aspect. 1 The category of mood, as we take it, dominates the category of tense. In the indicative mood there are (at least) three tenses, whereas in the "oblique" moods there are at any rate not more than two, and the imperative mood has no tenses at all. A peculiar relation obtains between the categories of number and of person. Leaving aside for the moment the verb be with its individual system of forms, number and person of English verbs have a positive (that is, non-zero) expression only in the -s-ending of the 3rd person singular present indicative. We might even suppose that in Modern English there are not two separate categories, number and person, but one "combined" number-person category. It is, however, doubtful whether such interpretation of phenomena would in any way yield a clearer and more consistent view of the verbal system. The notions of "number", that is, the difference between one and more-than-one doer, on the one hand, and that of "person", that is, distinction between the speaker, the one spoken to, and that which is neither speaker nor spoken to, seems too far apart, to be united under a common heading. In pursuing this subject further, it should be possible to work out a system of verbal categories, something of a "pyramid"; however, there would probably arise some doubts and difficulties in assigning a place to this or that category. б в. A. Ильиш