  A challenge towards developing NLP systems for the world's languages is
understanding how they generalize to typological differences relevant for
real-world applications. To this end, we propose M2C, a morphologically-aware
framework for behavioral testing of NLP models. We use M2C to generate tests
that probe models' behavior in light of specific linguistic features in 12
typologically diverse languages. We evaluate state-of-the-art language models
on the generated tests. While models excel at most tests in English, we
highlight generalization failures to specific typological characteristics such
as temporal expressions in Swahili and compounding possessives in Finish. Our
findings motivate the development of models that address these blind spots.
