Choose the correct answer to complete the sentence. " Carbon dioxide is one ---- the primary greenhouse gases that cause global warming."

Choose the correct answer to complete the sentence. "We must _____ that people are heavily polluting the environment."

Our house has been redecorated last week. You can still smell paint when you enter and the wallpaper has a striking contrast with the floor.

Forgetting something usually mean an inability to retrieve the material that is still stored somewhere in the memory.

Generally speaking, a magnitude 1.0 earthquake on the Richter scale is detected by instruments but not by person.

Without alphabetical order, dictionaries would be impossibility to use

One of the four underlined parts marked A, B, C, D in each sentence is not correct in standard English. Identify them: 

If we will reduce the speed of population growth, there will be less pressure on the earth. 

When scientists discovered how soap works, it became possible to do synthetic detergents out of Petroleum.

Industrialist Henry Ford introduced assembly-line techniques into the manufactures of motor vehicles.

Lan never goes out at night,  _    ?

The Vermont Elememary Science Project, according to its founders, are designed to challenge some of the most widely held beliefs about teaching 

What caused the explosion in the factory it is still unknown

Somehow without my noticing, my wallet had been disappeared

Because there was no evidence against himself, Slade was released

Many exercises such as calisthenics, running, or to swim involve producing muscle tension through a range of movements that are called isotonics.

Although there are more than 2,000 different variety of candy, many of them are made from a basis boiled mixture of sugar, water, and corn syrup

Every society changes, but not change at the same rate or in the same direction .

Algebra is the branch of mathematics concerned with operations on sets of numbers or other elements that are often represented at symbols

Most sand dunes are always in motion as wind pushes sand upward one side of each dune, over the top, and down the other side.

The early periods of aviation in the United States was marked by exhibition flights made by individual fliers or by teams of performers at country fairs

Marta being chosen as the most outstanding student of her campus made her parents very happy.