Usar "roos" en una oración

1. he boiled the roos in forty-four gallon drums and fed the

2. Roos, Hans, A History of Modern Poland: From the Foundation of the State in the First World War to the Present Day (Londres, 1966 [1961])

3. Beside these Ptolemaic ruins are found some traces of the prehistoric miners, and in a few cases as at the mines of the Um Roos these exist alone