Observing dark nebulae is difficult.

In this chemical experiment, we will examine the properties of benzoic acid.

He decided to challenge the exploration of the Dark Continent.

Dark matter is covering this world.

I have been to Antwerp.

A new arbor was built in the park.

The sovereign is the ruler of that country.

He resisted the temptation.

I was watching the sunset while listening to the sound of the waves on the beach.

He was able to spell the word correctly.