Reading ESL stories and readings in English for ESL learners

barcodes on some household products

Bar Codes and Lasers

Almost everything that we buy at a store now has a bar code on it. The patterns of black and white lines on a bar code are like a message written in a secret code. To decode the message we need special equipment. When we go through a checkout at a store the cashier uses a a bar code reader to check the price of everything we buy. The bar code reader decodes the data on a bar code. Bar code readers scan the bar codes and send the information to a computer. The computer then tells the cashier what the price is. Some scanners use a laser that is able to read the pattern of white and black lines on the bar code.

The physics of how a laser works is complicated. A laser emits a very narrow beam of light. This light hits the bar code and is then reflected back towards the scanner. The amount light that is reflected back to the scanner is greater if the surface is white and the amount reflected back is less if the surface is black. As a laser beam passes over a bar code it makes a pattern of reflected light. The scanner has a sensor that can tell how much light is being reflected. The scanner takes the information from the scanner and sends it to a computer. If the computer has the right software it can identify what product the code refers to and what the price of that product is.

Vocabulary help:

More vocabulary?  Click on the icon that looks like a book, to the left

Comprehension Check:

Did you understand the story? Are these sentences true?

1. Bar codes are on a lot of things that we buy at a store. Yes or no?

2. All scanners use a laser. Yes or no?

3. White lines reflect more light than black lines. Yes or no?

4. A sensor in the scanner can tell how much light is reflected back from the bar code. Yes or no?


Fill in the Blanks:

5. The scanner sends information to a ____________________.

6. A bar code is a ________________ of black and white lines.

7. To _____________ the information on a bar code we need a bar code ___________________.

8. A laser ______________ a very narrow beam of ________________.

>> Answers
beryl specimens on display in a glass case

Different types of beryls,

American Museum of Natural History, New York City

Beryl, Aquamarine and Emerald

Beryl is a mineral with long chemical name, beryllium aluminium cyclosilicate. Minerals are like rocks. They are naturally occurring solids with a crystalline structure. Beryl crystals are a hexagonal shape. These six sided crystals can be very small or they can be several meters in size. Pure beryl has no colour. Impure beryls come in different colours, green, blue, yellow, red or white. Different colours are made by different impurities.

Light blue beryls are called aquamarines. Small amounts of iron in beryl makes it blue. Aquamarine is found in the United States, Brazil, Pakistan and in many countries in Africa. Aquamarine can form large crystals that are flawless. They are perfectly formed.

If the element chromium is present in beryl crystals, the resulting beryls are green. These are emeralds. People have mined emeralds for centuries. The ancient Egyptians used emeralds as gem stones. Jewellers still use emeralds to make jewellery today. Emeralds usually only form small crystals and flawless emeralds are very rare. Because emeralds have flaws in them they break more easily that other beryls. The best emeralds are found in Columbia but emeralds are also mined in Brazil and in Pakistan.

Vocabulary help:

More vocabulary?  Click on the icon that looks like a book, to the left

Comprehension Check:

Did you understand the story? Are these sentences true?

1. Emeralds are hexagonal crystals. Yes or no?

2. Pure beryls come in different colours. Yes or no?

3. Aquamarines have chromium in them. Yes or no?

4. Beryls are mined in Pakistan. Yes or no?


Fill in the Blanks:

5. Beryls are ___________________ occurring minerals.

6. Aquamarines are often _____________________ but emeralds have cracks and other flaws.

7. The ancient ________________ mined emeralds.

8. Emeralds are often used to make ____________________.

9. The best emeralds are found in ______________________.

>> Answers
an assortment of household objects that are made of plastic

Plastics

If you brushed your hair or your teeth this morning then you used plastics. The handles of the hair brush and toothbrush were probably made of plastic. The bristles on both brushes were probably made of nylon. Nylon is a type of plastic.

Plastic is everywhere and we use plastic every day. There may be plastics in your shoes, your furniture and your clothes. When you ride in a car or on a bus, train or airplane you are surrounded by plastic. Because plastic can be made into almost any shape it is a very useful material. We can make plastic bottles, plastic cutlery and plastic containers. Your phone and your computer contain plastic parts too.

If you buy take out food from a restaurant it is probably in a white container. This is styrofoam, a type of plastic that has air bubbles in it. Not all plastics are hard. There are plastics in some paints and glues that are thick liquids.

Vocabulary help:

More vocabulary?  Click on the icon that looks like a book, to the left

Comprehension Check:

Did you understand the story? Are these sentences true?

1. Styrofoam is a plastic that is white. Yes or no?

2. All plastics are hard. Yes or no?

3. Plastic can be made into any shape. Yes or no?

4. Nylon is a type of plastic. Yes or no?

5. We use plastics every day. Yes or no?

>> Answers
an assortment food that contains large amounts of starch such as cookies, pasta, cereal, flour and bread

Many of the foods we eat contain sugars and starches.

 

Sugars and Starches

Bread, cookies, cereals, pasta, noodles and cakes are some of the things that people like to eat. They contain a lot of sugars and starches. In fact, sugars and starches are the major source of energy for most people. We eat a lot of it. Sugars and starches are also called carbohydrates, often shortened to just "carbs". We get most of our carbohydrates from plants. Sugar comes from sugar cane or from sugar beets. Honey is also a source of sugars. Wheat, rice, potatoes and corn are good sources of starches.

Starch is just a long strand of sugars joined together. When we eat starch our body is able to break down, or digest, the starch into sugar. Digestion of starch starts on your tongue. If you put a cracker or a piece of bread on your tongue and leave it there for a short time it will start to taste sweet.

Vocabulary help:

Comprehension Check:

Did you understand the story? Are these sentences true?

1. Starch is made of sugars. Yes or no?

2. Sugars and starches are called carbs. Yes or no?

3. There is no sugar or starch in bread. Yes or no?

4. Wheat is a good source of starch. Yes or no?

5. We get most of our carbohydrates from animals. Yes or no?


Fill in the Blanks:

6. Sugar and starches are a major source of ________________ for people.

7. Digestion of starch starts on your __________________.

8. Sugars taste ________________.

>> Answers
four wind turbines on a farm

Wind turbines in southwestern Ontario.

 

 

 Electricity from the Wind

People are looking for news ways of making electricity that are inexpensive and don’t harm the environment. One way is to make electricity using the wind. Wind turbines are built in areas where there is lots of wind. When the wind blows, the blades of the turbines spin. The energy generated by this spinning is changed to electricity.

There are people who like wind generated power but there are many people who dislike it. The wind is free but the turbines that make the electricity are expensive to build. Wind energy makes no water pollution or air pollution but the turbines make noise. Some people say that the noise can harm the people who live near the wind farms.

Vocabulary help:

More vocabulary?  Click on the icon that looks like a book, to the left

Comprehension Check:

Did you understand the story? Are these sentences true?

1. Some people do not like wind generated power. Yes or no?

2. Wind turbines are inexpensive to build. Yes or no?

3. Wind energy pollutes the air. Yes or no?

>> Answers
 group shot of an extended family

Genes

Although all people share some of the same characteristics, there are enough differences to make us unique. Some of us are taller than others. We can have different coloured eyes, blue eyes, brown eyes, grey eyes, or black eyes. Some people never seem to get sick while other people catch colds easily. Characteristics such as freckles, skin colour and hair colour also differ between people. Some of us have crooked noses. We can have long thin fingers or short thicker fingers.

The characteristics that we have are determined by our genes. Our genes carry the information that makes us what we are. We all have two sets of genes that we inherit from our parents, one from our mother and the other from our father. Genes are made of DNA. All the cells in our body have the same genes and the same DNA.

 Many characteristics such as eye colour are determined only by our genes. Other characteristics are affect by other things too. For example, our genes help determine how tall we will grown, but having enough healthy food when we are children will also affect our growth.

 

Vocabulary help:

More vocabulary?  Click on the icon that looks like a book, to the left

Comprehension Check:

Did you understand the story? Are these sentences true?

1. Eye colour, skin colour and height are characteristics of people. Yes or no?

2. Some people have freckles but some people don't. Yes or no?

3. Some cells in your body have different DNA than other cells. Yes or no?

4. All of our genes come from our mothers. Yes or no?


Fill in the blanks:

5. The food that children eat helps determine how ________ they will grow.

6. The characteristics that people have are determined by their ______________.

7. You have ________ sets of genes.

8. People have different coloured __________. Some are blue, some are brown and some are black.

9. We _____________ our genes from our parents.

10. Our genes are made of _______________.

>> Answers

Answers:


Bar Codes and Lasers

1. yes, 2. no, 3. yes, 4. yes

5. compter, 6. pattern or code, 7. decode/reader, 8. emits/light

Back ^


Beryl, Aquamarine and Emerald

1. yes, 2. no, 3. no, 4. yes,

5. naturally, 6. flawless (or perfect), 7. Egyptians, 8. jewellery, 9. Columbia

Back ^


Plastics

1. yes, 2. no, 3. yes, 4. yes, 5. yes

Back ^


Sugars and Starches

1. yes, 2. yes, 3. no, 4. yes, 5. no,

6. energy 7. tongue 8. sweet

Back ^


Electricity from the Wind

1. yes, 2. no, 3. no

Back ^


Genes

1. yes, 2. yes, 3. no, 4. no,

5. tall, 6. genes, 7. two, 8. eyes, 9. inherit, 10. DNA

Back ^