He made a model of a regular icosahedron.

The National Aeronautics and Space Administration announced a new space exploration plan.

My dream is to go to the U.S. Virgin Islands.

He read ten books.

I went to the market accompanied by my mother.

My son participates in judo practice every day.

This is an important problem.

It takes twenty minutes to get to my house.

Deuterium is one of the isotopes of hydrogen.

A new polymer was produced by this chemical reaction.