Determining whether a given work is in or out of copyright can be a complicated task.

You can't blame yourself when things go wrong in a complicated task such as this.

The design of such systems, however, is a complicated task.

But recovering their lost credibility may be a more complicated task.

This was a complicated and sophisticated task, which later took the Americans some time to master.

Making a marker is a complicated task, even with modern computer assistance.

I believe it was a complicated task which has been successful.

This is only the beginning, and we are facing an extremely complicated task.

But to do so would be a complicated task.

Deciding the priorities was a very complicated and difficult task.