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Speech Patterns

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Speech Patterns

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1. Fossil fuels were formed from ____.

a) ancient plants and animals b) carbon c) water

2. Chemically fossil fuels are ___.

a) compounds of oxygen b) acids c) hydrocarbons

3. When these fuels burn they ___ energy.

a) annihilate b) absorb c) release

Text 2. Where do Rainbows Come from?

Light bends as it travels from one location to another, due to the different speeds at which it travels through different mediums. This process of natural bending is referred to as refraction. When light passes through a prism, the different colours of the light refract out at different angles, dispersing and becoming individually visible to the human eye. The same principle applies when light passes through a droplet of water in the air. If enough light passes through enough droplets in a confined area, the refracted pattern of light is visible to humans as a bent stripe of multiple colours, known everywhere as a rainbow.

1. Refraction is the process of natural ___ of light.

a) shining b) dissolution c) bending

2. When light passes through a prism, one can see different ___.

a) pictures b) colours c) movies

3. A rainbow is light passing through ___.

a) elementary particles b) a mountain c) droplets of water

Text 3. Where Does Metal Come From?

Most metal is mined straight out of the earth in the form of ore. Ore is any part of the Earth’s crust, often a mixture of rocks, loose soil and other earthy materials, from which a valuable material can be extracted. This can be difficult, since the desirable metal is often locked in chemical compounds with other unwanted materials and filled with impurities. Ore refiners must find the best way to separate each useful element from the rest of the ore in which it lies. One common method of extraction is smelting, which is where refiners heat the ore to extremely high temperatures with the use of powerful furnaces. This makes it easier to get the pure metals out. In the refining of iron, for instance, the smelting process releases unwanted particles of oxygen that populate raw iron ore.

1. Most metals are extracted from ___.

a) ore b) ear c) air

2. Ore always contains ___.

a) all the chemical elements b) some impurities c) only pure metal

3. To get the pure metal metallurgists use special ___.

a) furniture b) furnaces c) solvents

Text 4. How Did the Computer Mouse Come into Being?

The development of the computer mouse as an essential input device followed on the heels of numerous changes to the operating environment of personal computers. Initially, there was no need for a mouse, because there was nothing to point to on a computer screen. Early computers had primitive interfaces that used crude methods to receive data, like punch cards or teletype machines. Once graphical user interfaces were created, however, and pointing became an essential part of interacting with a computer, the mouse soon became the input device of choice in personal computing. The first mouse to have commercial success debuted with Apple’s Macintosh computer in 1984.

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