Two-moras-cluster as a rhythm unit in spoken Japanese sentence or verse

要旨

In spoken Japanese sentence, mora is regarded as a temporal unit because of its isochronous tendency. However, in slowly spoken Japanese sentence or verse, two moras tend to be read as one cluster and the isochrony of more looks gone. So the cluster comes up as a rhythm unit. This tendency is quite clear in recitation of verse. Some people have taken notice to such a phenomenon, but nobody confirmed it by physical measurement. Here, durations of moras are measured systematically according to speaking speed, in order to study how the cluster consists of two moras. As a result, it is found out that a waiting interval comes up between the second mora in the cluster and the first mora of the next cluster, whenever the speed comes fairly slow. During the waiting interval, voicing action usually still continues. So, the apparent duration of the second more looks longer than the first one. This is the reason why the waiting intervals have never been revealed unless they are studied and measured systematically.

主題