He was hiding the fact that he was an illegitimate child.

The cause of his lateness was a train delay.

Scientists are advancing research on nuclear fusion.

His name is a proper noun, known all over the world.

Because of his indecisive nature, he always takes a long time to choose a menu at a restaurant.

This beautiful zoisite necklace is my favorite.

A cellar spider is making a web in the corner of the room.

In this experiment, we will observe the reaction of organic compounds.

He wants to learn about the life of nomads.

He looked around in all directions, but there was no one.