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985. A neuter plural subject is regarded as a collective (996), and has its verb in the singular: καλα ην τα σφαγια the sacrifices were propitious X. A. 4.3.10.

N. — The neuter plural seems to have been originally in part identical in form with the feminine singular in -ā, and to have had a collective meaning.

959. A plural verb may be used when stress is laid on the fact that the neuter plural subject is composed of persons or of several parts: τα τελη των Λακεδαιμονιων αυτον εξεπεμψαν the Laceddaemonian magistrates despatched him T. 4.88, φανερα ησαν και ιππων και ανθρωπων ιχνη πολλα many traces both of horses and of men were plain X. A. 1.7.17.

a. With the above exception Attic regularly uses the singular verb. Homer uses the singular three times as often as the plural, and the plural less frequently with neuter adjectives and pronouns than with substantives. In some cases (B.135) the meter decides the choice.