Guttural R
Many Jewish immigrants to Israel spoke a variety of Arabic in their countries of origin and pronounced the Hebrew rhotic as an alveolar tap , similar to Arabic '. Gradually, many of them began pronouncing their Hebrew rhotic as a voiced uvular fricative , a sound similar or (depending on the Arabic dialect) identical to Arabic '. However, in modern Sephardic and Mizrahi poetry and folk music an alveolar rhotic continues to be used.
Samaritan Hebrew
For the Samaritans, Ancient Hebrew ceased to be a spoken everyday language and was succeeded by Samaritan Aramaic, which itself ceased to be a spoken language some time between the 10th and 12th centuries and was succeeded by Arabic (or more specifically Samaritan Palestinian Arabic).