Instructions:

Articulator: the back of the tongue

Point of Articulation: Uvula

Manner: When the air from the lungs goes over the articulator, which is positioned close to (but not touching) the point of articulation, vibrations occur between the articulator and the point of articulation.

Voice: voiced – Vocal folds are close and vibrating.

Occurrence: Afrikaans (some dialects), Catalan (some northern dialects), Dutch (Belgian Limburg, Central Netherlands, Randstad, Southern Netherlands, Flemish Brabant, Northern Netherlands, West Flanders), English (Cape flats dialect, Northumbrian dialect, Sierra Leonean), French, Standard German, Hebrew, Italian (Northern dialects), Judaeo-Spanish, Occitan (Eastern dialects, Provencal dialect, Southern Auvergnat dialect, Southeastern Limousin dialect), dialects of Portuguese (European, Fluminense, Sulista), Romani (some dialects), Selkup (Northern dialects), Sioux (Lakota), Sotho (most speakers), Swedish (southern).
(Source: https://en.wikipedia.org/wiki/Uvular_trill#Occurrence)