Spectroscopy is an important means of investigating the properties of matter.

He is an expert in Classical Chinese text studies, and is good at interpreting ancient Chinese literature.

He is knowledgeable in all fields of learning.

He is widely recognized as an expert in dogmatics.

He is majoring in the study of national law.

He understands the basic concepts of thermodynamics.

The National Research and Development Agency plays a crucial role in advancing science and technology.

She was a secret kunoichi (female ninja).

He threw a handful of sand into the sea.

"Once in a lifetime" means to cherish the encounter that happens only once in one's lifetime.