This new software maintains upward compatibility with the old version.

These two software have complete interchangeability.

Cats are digitigrade animals, they walk on their toes.

He learned about unguligradism in his zoology class.

His research mainly focuses on the plantigradism of mammals.

She has polycystic ovary syndrome.

He is writing a thesis on monotheism.

Sufficient caution is necessary when handling radioactive materials.

He said, 'Even if you die in the evening, it's okay if you ask the way in the morning,' teaching me the importance of living each day to the fullest.

General relativity is a theory of physics proposed by Einstein.