For further discussion of this verse form, see Roland Steiner, “Die Lehre der Anuṣṭubh bei den indischen Metrikern,” in Suhr̥llekhāḥ: Festfabe für Helmut Eimer, ed. by Michael Hahn, Jens-Uwe Hartmann and Roland Steiner, pp. 227–48 (Swisttal-Odendorf: Indica et Tibetica Verlag, 1996).
The so-called anuṣṭubh ślōka is a verse (ślōkaḥ) that belongs to the anuṣṭup class of syllable-counting meters (vr̥ttāni), which contains four lines of eight syllables each, or 4 × 8 = 32 syllables in total.
The ślōka is the most common meter in all of Sanskrit literature. It is also, partly, in a class by itself. Whereas most of the other meters that are used in Sanskrit regulate the weight of every single syllable in the verse line, the ślōka regulates the weight of its syllables in a slightly different way, explained below. It is one of the few forms of Vedic meter to survive in common use in the classical period (the other being the upajāti, which is continuous with the Vedic triṣṭubh).
The ślōka basically has two types of patterns: one that operates in odd lines (i.e., pādas 1 and 3), and the other that operates in even lines (i.e., pādas 2 and 4). They will be explained in turn. The most general form, however, can be schematized as follows:
According to the analysis given by Piṅgala and others, the “normal” form (pathyā) of the odd lines of the ślōka has the following form (where × represents any syllable, heavy or light, while । represents a light syllable, and ऽ represents a heavy syllable):
× × × × । ऽ ऽ ×
This is the most common form, but there are a number of “extensions” (vipulā) that are referred to by the trikas representing syllables 5, 6, and 7:
× × × × ऽ । । ×
× × × × ऽ । ऽ ×
× × × × । । । ×
× × × × ऽ ऽ । ×
Even lines (Samapādau)
In the even lines, the ślōka conforms to the following pattern (where, once again, × represents any syllable, heavy or light, while । represents a light syllable, and ऽ represents a heavy syllable):
× × × × । ऽ । ×
Note that the final syllable of an even line is always considered to be metrically heavy, so the ending of the even lines of the ślōka will always have the iambic rhythm ।ऽ।ऽ.
This example was recited by H.V. Nagaraja Rao and recorded by Nathan Levine in Toronto in 2018. The recordings were uploaded to archive.org by Anusha Rao. The translation is my own.