He is writing a letter.

The baby is waving its hands and laughing.

He held a new book in his hand.

He waved his hand.

He is an expert in systems engineering.

Our school has introduced a new PA system.

The filesystem of my computer has broken down.

The automotive navigation system in my car has downloaded the latest map data.

Geographic Information Systems are very useful tools for map making and spatial data analysis.

I was captivated by her beautiful figure.