"And, Sariputra, that Thus Come One has an immeasurable Sound Hearer assembly, of which pure Arhats the number is not easy to tell. With such arrays of qualities of a Buddhaland, Sariputra, is this Buddhaland adorned." (9) Sakyamuni Buddha says to sariputra: ca "and", then literally "of that Thus Come One" -- tasya and tathagatasya being genitive singular -- "there is an" (not expressed in Sanskrit) aprameyah "immeasurable" sravaka "Sound Hearer" (see VBS #39) sangho "assembly" (see VBS #35). In English "Thus Come One" can be the subject of a possessive verb though, as translated above. He continues: yesam "of which" -- genitive plural masculine, whose antecedent is sravaka, understood to be plural although without a case ending since it is the first member of a compound. This pronominal adjective introduces a relative clause whose subject is pramanam "number/measure" (see VBS #123), nominative singular neuter. No verb "is" appears. The predicate, negated by na "not", is sukaram "easy", which governs the infinitive akhyatum "to tell." Suddhanam "(of) pure/purified" is genitive plural masculine, agreeing with arhatam "(of) Arhats" (see VBS #40). Literally the Sanskrit reads this way, but you could say "Sound Hearers, pure Arhats, whose number is not easy to tell." It's not a simple matter to count the number of Arhats, because an additional quality of the Buddha Limitless Life (Amitayus), also called Limitless Light (Amitabha), is that his assembly of Sound Hearer disciples is also limitless.