My grandfather works in the cultivated field every day.

He announced his marriage by official telegram.

A flash of lightning illuminated the sky.

My father is an electrician.

The photoelectric effect is a phenomenon where a material emits electrons after absorbing light.

The rearguard is a role that is positioned at the end of the team.

I want to spend time with you anytime.

A salt pan is an important facility for making salt from seawater.

The electromagnetic waves in this room are too strong, causing the electronic devices to malfunction.

A positron is a particle that carries a charge opposite to that of an electron.