In the physics experiment, we observed the reflection of light using a concave mirror.

There is a three-way interview at my son's school tomorrow.

People with strong general immunity are less likely to catch a cold.

Mucosal immunity plays a crucial role in protecting our bodies from pathogens.

This regular dodecahedron is a geometric shape with perfect symmetry.

He made a model of a regular dodecahedron.

He made a model of a regular icosahedron.

This solid is called a regular icosahedron, and it is made up of 20 equilateral triangles.

Memphis is an ancient city in Egypt.

He conducted an experiment using a spherical lens.