Nuclear fission is a powerful phenomenon that generates energy.

He observed the stars using a sextant for navigation.

We conducted a spectral analysis to investigate the spectral characteristics of this substance.

The Cultural Revolution is a part of China's history.

His father was diagnosed with schizophrenia in the past.

He was diagnosed with schizophrenia.

The meristem of this plant is very active.

This document contains environment-dependent characters.

This old television uses a cathode ray tube.

He is irritable like a tantrum ball.