He is an expert in systems engineering.

Our school has introduced a new PA system.

The filesystem of my computer has broken down.

He has a very passive personality.

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.

His advice was very practical.

His target-like way of thinking is hard to understand.

He is my biggest enemy.

What is that target?