We need to adjust the descent speed of the helicopter.

When you're ready, jump!

The snow is falling quietly.

Education about sex is very important.

In physics, the study of the 'nucleus' at the center of an atom is important.

My past has made me stronger.

We conducted a new experiment in science class.

Sufficient caution is necessary when handling radioactive materials.

Radioactive elements are produced in nature and scientific experiments.

This area is off-limits due to high radiation levels.