Mining over 2,000 years ago, copper is one of the earliest known metals.

All the studentsare looking forward spending their free time relaxing in the sun this summer.

Some jellyfish make daily journeys from deep water to the surface and back, while others migrate horizontal.

I’m so tired; I’m finding it difficult in keeping my mind on my work.

The average temperature on Mars, the fourth planet from the Sun, is about eighty degrees than colder on Earth.

In about, experimental psychologists have devoted more research to learning than to any other topic.

Early radio was called the “wireless” because radio uses invisibly waves to carry information.

The girls were sorry to had missed the signers when they arrived at the airport.

The first postage stamp, issued on May 6th 1860 in England, is was the Penny Black, which featured a profile of Queen Victoria.

Photographs from a satellite are frequently used to generate the information is needed to produce a map

In order no money would be wasted, we had to account for every penny we spent.

The firstly naval battle of the Revolutionary War was fought off the coast of Machias, Maine, in June 1775.

Protecting Florida’s coral reefs is difficult because some of the corals are very fragile even the touch of a diver’s hand can kill it.

Choose the word which has a different stress pattern from the others.

In the architecture, a capital is the top portion of a column

The average cat sleeps  sixteen hours for a day in short intervals called ‘cat naps'.

All of the students_______ the seniors will receive their grades in two weeks.

We are not allowed to enter this construction site. A block of flats is being built here and it is dangerous to walk because you may get hurt by a fallen brick or some other objects.

The teacher taught her students to look careful to the left and the right at least three times before crossing the highway.

When her son, Nick fell and injured his knee, she refused to pay for a doctor and spent hours looking up free medical help.

Until recently, women were forbidden by law owning property