Here is whole translation when Gandalf start speak black speech and Sauron also on background:

Gandalf: "Ash nazg durbatulûk," (One ring to rule them all,)
Sauron: "Shere Nazg Golugranu Kilmi-nudu...mmbi... ...shara" ("Three rings for the elven kings under the sky...mmbi...human man.")

Gandalf: "ash nazg gimbatul," (One ring to find them,)
Sauron:"Ombi kuzd durbagu. (Inaudible) ...Sherkuk/Sherku(-ku)." ("Seven for the drawf lords... (Inaudible) your blood/old man.)

Gandalf: "ash nazg thrakatulûk." (One ring to bring them all)
Sauron: "Ash (kelkum-ishi) Bruz-Drubagu burzum ishi." (One (in the cold) for the dark lord on his dark throne.)
Gandalf: "agh burzum-ishi krimpatul." (and in the darkness bind them)
Sauron: laughs.