I'm troubled by his unproductive attitude.

He was affected by secondary effects.

This is a preliminary plan.

Thinking sensibly, that plan will not succeed.

He is interested in diachronic linguistics studies.

He is interested in synchronic linguistics.

He is thought to be a very unsociable person.

My friend is working in the United Arab Emirates.

The German Democratic Republic was once a socialist country.

My dream is to visit the Federal Republic of Germany someday.