In the first example, a noun (a substantive) fills the “subject” syntactic function slot, whereas in the second example, an infinitive that is functioning as a substantive fills the “subject” syntactic function slot. We could also substitute some other parts of speech into this “subject” function slot, such as the participle “singing”27: “Singing brings great joy to us.” But we could not substitute a verb, such as “sings,” into this “subject” function slot: “Sings brings great joy to us.” Thus the