Commercial airliners do not fly in the vicinity of volcanic eruptions because even a small amount of volcanic ash can damage its engines.

He was so careless that he left the work half doing and went to the cinema.

In summer, warm southern air carries moist north to the eastern and central United States.

After analyzing the steep rise in profits according to your report, it was convinced that your analyses were correct.

Either Mr. Anderson or Ms. Wiggins are going to teach our class today as our teacher has been staying in hospital.

Weather and geographical conditions may determine the type of transportation using in a region.

What happened in that city were a reaction from city workers including firemen and policemen who had been laid off from their jobs.