tens of thousands of german jewish refugees 
(ROOT (NP (NP (NNS tens)) (PP (IN of) (NP (NP (NNS thousands)) (PP (IN of) (NP (JJ german) (JJ jewish) (NNS refugees)))))))
(ROOT (NP (NP (NNS )) (PP (IN ) (NP (NP (NNS )) (PP (IN ) (NP (JJ ) (JJ ) (NNS )))))))