To his surprise, the engine started by first try.

In the sixteenth century, Francois Vieta, a French mathematician, used vowels “a”, “e”, “i”, “o”, “u” to represent a unknown number.

As the plane went more faster the runway, David began to sweat nervously.

Carrie Chapman Call organized the League of Women Votes after successfully campaign for the constitutional amendment that gave women right to vote.

Do you know the reason ……. humans are interested in Mars and other planets in thesolar system?

Each chemical element is characterized to the number of protons that an atom of that element contains, called its number.

Don’t let him treat you badly. _____ him. 

I am the first person to be interviewed, _____?

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

Marie, ................ I met at the party, called me last night.

Do you think that  the humans will ever be able to live in other planets?

A pack of wild dogs ………… frightened all the ducks away

The cars in garage were badly need of to be repaired

In the 1920’s, cinema became an important art form and one of ten largest industry the United States.

You have ever heard about Yuri Gagarin, ____?

In 1991, Antonia Novello, Unites States Surgeon General launched several programs to address particular problem that young people have.

If the Oxygen supply in the atmosphere was not replenished plants, it would be exhausted

Let’s do something to protect the environment, _____ we?

All of  the mammals, dolphins are undoubtedly among friendly to human.

Though he did not develop language, Laurent Clerc brought it on America from France.

Nitrogen must be combine with element such as Hydrogen or Oxygen to be useful in agriculture or industry.