Please tell us the reason when he left without saying goodbye.

Mai and Lan have a row because they have misunderstood one another.

Robots in the home might not be enough creative to do the cooking, plan the meal and so on.

He is the second person be killed in that way.

My father asked me where had I gone the night before.

Society uses such human emotions as proud, shame, guilt, and fear to maintain itself.

Two weeks are plenty of time to finish the assignment.

It is time the government do something to help the unemployed to find some jobs.

Developing new technologies are time-consuming and expensive.

Oxygen plays a important role in maintaining live.

Unlike many writings of her time, she was not preoccupied with morality.

After the police had tried unsuccessfully to determine to who the car belonged, they towed it to the station.

Air pollution, together with littering, are causing many problems in our large, industrial cities today.

When a patient's blood pressure is much higher than it should be, a doctor usually insists that he will not smoke.

Mary and her sister just bought two new winters coats at the clearance sale.

It is difficult to write rules that tell exactly when we should apologize, and it is not difficult to learn how to do it.

How much times did Rich and Jennifer have to do the experiment?

My teacher is very strict and he always makes us to finish all the exercises before leaving school.

Despite the long history of the rights of property ownership, there have been a great deal of disagreement over what such rights entail.

Did you say that you will have a lot of things to do the following week?

The master of ceremonies announced in a loud and clear voice and told that the dinner would be late due to unforseen circumstances.