Change any of these features of the sentence and it becomes modified, slightly or seriously, in some purely relational, non-material regard.  If the is omitted (farmer kills duckling, man takes chick), the sentence becomes impossible; it falls into no recognized formal pattern and the two subjects of discourse seem to hang incompletely in the void.  We feel that there is no relation established between either of them and what is already in the minds of the speaker and his auditor.  As soon as a the is put before the two nouns, we feel relieved.  We know that the farmer and duckling which the sentence tells us about are the same farmer and duckling that we had been talking about or hearing about or thinking about some time before.  If I meet a man who is not looking at and knows nothing about the farmer in question, I am likely to be stared at for my pains if I announce to him that “the farmer [what farmer?] kills the duckling [didn’t know he had any, whoever he is].”  If the fact nevertheless seems interesting enough to communicate, I should be compelled to speak of “a farmer up my way” and of “a duckling of his.”  These little words, the and a, have the important function of establishing a definite or an indefinite reference.

If I omit the first the and also leave out the suffixed _-s_, I obtain an entirely new set of relations. Farmer, kill the duckling implies that I am now speaking to the farmer, not merely about him; further, that he is not actually killing the bird, but is being ordered by me to do so.  The subjective relation of the first sentence has become a vocative one, one of address, and the activity is conceived in terms of command, not of statement.  We conclude, therefore, that if the farmer is to be merely talked about, the little the must go back into its place and the _-s_ must not be removed.  The latter element clearly defines, or rather helps to define, statement as contrasted with command.  I find, moreover, that if I wish to speak of several farmers, I cannot say the farmers kills the duckling, but must say the farmers kill the duckling.  Evidently _-s_ involves the notion of singularity in the subject.  If the noun is singular, the verb must have a form to correspond; if the noun is plural, the verb has another, corresponding form.[54] Comparison with such forms as I kill and you kill shows, moreover, that the _-s_ has exclusive reference to a person other than the speaker or the one spoken to.  We conclude, therefore, that it connotes a personal relation as well as the notion of singularity.  And comparison with a sentence like the farmer killed the duckling indicates that there is implied in this overburdened _-s_ a distinct reference to present time.  Statement as such and personal reference may well be looked upon as inherently relational concepts.  Number is evidently felt by those who speak English