I often go birdwatching in the park on weekends.

He committed another crime while on probation.

The shape of this crystal lattice is very unique.

This salt contains water of crystallization.

He is an expert in crystallography.

These test results are showing unexpected outcomes.

We analyzed the data of the experimental group.

He has a deep interest in empirical science.

The experimenter analyzed the data in detail.

Animal experiments are necessary for the advancement of science, but there are also ethical issues.