He tumbled off his horse.
Since the 1930s,aircraft manufacturers have tried to build airplanes with frictionless wings so that the air passing over them would not become turbulent.
This department has the highest turnover rate in the company.
Ted wants someone to tutor him before the exam.
The tutor would explain his mistakes to him.
You could stay up all night trying to count all the stars that twinkle in the sky.
We cannot see ultraviolet light in our atmosphere.
Janet was elected chairwoman by a unanimous decision of the board.
The newspaper article uncovered the truth behind the scandal.
The value of our house was underestimated by at least two thousand dollars.
Lack of money was the underlying reason that I didn't go on vacation.