Before went abroad, he had finished his English course at the English-speaking Center.

The clerks who are happy to wait for their customer will get promoted soon.

Because blood from different individuals may different in the type of antigen on the surface of the red cells and the type of antibody in the plasma, a dangerous reaction can occur between the donor and recipient in a blood transfusion.

The assumption that smoking has bad effects on our health have been proved.

What we know about certain diseases are still not sufficient to prevent them from spreading easily among the population.

The children next door are a real nuisance. Their football is always coming on the fence and damaging the flowers in my garden.

The office manager insists that his staff use all of their vacation time, but he hardly never takes a vacation himself.

Do most boys and girls give a great deal of thought to their future employ?

For the first time in the history of the country, the person which was recommended by the president to replace a retiring justice on the Supreme Court is a woman.

Narcissus, a character in mythology, gazed at his own image in a pool so ardently that he fell into itself and downed.

You shouldn’t criticize him in front of his friends. It was insensitive of you.

The Commitments of Traders Report is released by the Commodity Futures Trading Commission on eleventh day of each month.

The chemistry instructor explained the experiment in such of a way that it was easily understood.

A warning printed on a makeshift lifebuoy says: “This is not a life-saving device. Children should be accompany by their parents.”

I enjoyed talking to the people with that I met at the party last night.

The company did not want to hire a man that his experiment was so limited.

If you need to keep fit, then why not take on a sport such as badminton or tennis?

There are some people in the government try to improve the lives of poor people.

Ecologists are trying to preserve our environment for future generations by protecting the ozone layer, purifying the air, and have planted the trees that have been cut down.

Women in many parts of the world have had lower status than men, which the extent of the gap between genders varies across cultures and times.

Regarding as one of the leading figures in the development of the short story, O Henry is the author of many well- known American novels.