SINTESIS DE PERIODO

FORTH Grade

English

Simple PastFORM

[VERB+ed] or irregular verbs

Examples:

You called Debbie. Did you call Debbie? You did not call Debbie.

Complete List of Simple Past Forms

USE 1 Completed Action in the Past

Use the Simple Past to express the idea that an action started and finished at a specific time in the past. Sometimes, the speaker may not actually mention the specific time, but they do have one specific time in mind.

Examples:

I  saw a movie yesterday. I  didn't see a play yesterday. Last year, I traveled to Japan. Last year, I didn't travel to Korea. Did you have dinner last night? She washed her car. He didn't wash his car.

USE 2 A Series of Completed Actions

We use the Simple Past to list a series of completed actions in the past. These actions happen 1st, 2nd, 3rd, 4th, and so on.

Examples:

I  finished work, walked to the beach, and found a nice place to swim.

He arrived from the airport at 8:00, checked into the hotel  at 9:00, and met the others at 10:00.

Did you add flour, pour in the milk, and then add the eggs?USE 3 Duration in Past

The Simple Past can be used with a duration which starts and stops in the past. A duration is a longer action often indicated by expressions such as: for two years, for five minutes, all day, all year, etc.

Examples:

I  lived in Brazil for two years. Shauna studied Japanese for five years. They sat at the beach all day. They did not stay at the party the entire time. We talked on the phone for thirty minutes. A: How long did you wait for them?

B: We waited for one hour.USE 4 Habits in the Past

The Simple Past can also be used to describe a habit which stopped in the past. It can have the same meaning as "used to." To make it clear that we are talking about a habit, we often add expressions such as: always, often, usually, never, when I was a child, when I was younger, etc.

Examples:

I  studied French when I was a child. He played the violin. He didn't play the piano. Did you play a musical instrument when you were a kid?

She worked at the movie theater after school. They never went to school, they always skipped class.

Present PerfectFORM

[has/have + past participle]

Examples:

You have seen that movie many times. Have you seen that movie many times? You have not seen that movie many times.

Complete List of Present Perfect Forms

USE 1 Unspecified Time Before Now

We use the Present Perfect to say that an action happened at an unspecified time before now. The exact time is not important. You CANNOT use the Present Perfect with specific time expressions such as: yesterday, one year ago, last week, when I was a child, when I lived in Japan, at that moment, that day, one day, etc. We CAN use the Present Perfect with unspecific expressions such as: ever, never, once, many times, several times, before, so far, already, yet, etc.

Examples:

I  have seen that movie twenty times. I think I have met him once before. There have been many earthquakes in California. People have traveled to the Moon. People have not traveled to Mars. Have you read the book yet? Nobody has ever climbed that mountain. A: Has there ever been a war in the United States?

B: Yes, there has been a war in the United States.

How Do You Actually Use the Present Perfect?

The concept of "unspecified time" can be very confusing to English learners. It is best to associate Present Perfect with the following topics:

TOPIC 1 Experience

You can use the Present Perfect to describe your experience. It is like saying, "I have the experience of..." You can also use this tense to say that you have never had a certain experience. The Present Perfect is NOT used to describe a specific event.

Examples:

I  have been to France.THIS SENTENCE MEANS THAT YOU HAVE HAD THE EXPERIENCE OF BEING IN FRANCE. MAYBE YOU HAVE BEEN THERE ONCE, OR SEVERAL TIMES.

I  have been to France three times.YOU CAN ADD THE NUMBER OF TIMES AT THE END OF THE SENTENCE.

I  have never been to France.THIS SENTENCE MEANS THAT YOU HAVE NOT HAD THE EXPERIENCE OF GOING TO FRANCE.

I think I have seen that movie before. He has never traveled by train. Joan has studied two foreign languages. A: Have you ever met him?

B: No, I have not met him.TOPIC 2 Change Over Time

We often use the Present Perfect to talk about change that has happened over a period of time.

Examples:

You have grown since the last time I saw you. The government has become more interested in arts education. Japanese has become one of the most popular courses at the

university since the Asian studies program was established. My English has really improved since I moved to Australia. Already means that something happened earlier than we

expected. With Present Perfect already usually goes after have or has and before the main verb.

Examples 

   - We've already had our breakfast. 

   - When are you going to do your homework?   - But I've already done it! 

   - Do you want a cup of coffee?   - No, thanks. I've already had one."

Yet means that something that we expected has happened or hasn't happened. We usually put it at the end of a sentence.

Examples 

   - Has the post arrived yet? 

   - Have you done your homework?   - Not yet.

   - Haven't you got ready yet? Look at the time!

SCIENCE

Work

refers to an activity involving a force and movement in the directon of the force. A force of 20 newtons pushing an object 5 meters in the direction of the force does 100 joules of work.

Energy

is the capacity for doing work. You must have energy to accomplish work - it is like the "currency" for performing work. To do 100 joules of work, you must expend 100 joules of energy.

Power

is the rate of doing work or the rate of using energy, which are numerically the same. If you do 100 joules of work in one second (using 100 joules of energy), the power is 100 watts.

Index

Work concepts

HyperPhysics***** Mechanics R NaveGo Back

Work-Energy Principle

The change in the kinetic energy of an object is equal to the net work done on the object.

This fact is referred to as the Work-Energy Principle and is often a very useful tool in mechanics problem solving. It is derivable from conservation of energy and the application of the relationships for work and energy, so it is not independent of theconservation laws. It is in fact a specific application of conservation of energy. However, there are so many mechanical problems which are solved efficiently by applying this principle that it merits separate attention as a working principle.

For a straight-line collision, the net work done is equal to the average force of impact times the distance traveled during the impact.

Average impact force x distance traveled = change in kinetic energyIf a moving object is stopped by a collision, extending the stopping distance will reduce the average impact force.

Car crash example Seatbelt useAuto stopping distance

Large truck-small truck collision

Two trucks, equal momentum

Impact force of falling object

SOCIAL STUDIES

FAST FACTS

OFFICIAL NAME: CanadaFORM OF GOVERNMENT: Federal parliamentary stateCAPITAL: OttawaPOPULATION: 34,834,841OFFICIAL LANGUAGES: English, FrenchMONEY: Canadian dollarAREA: 3,849,674 square miles (9,970,610 square kilometers)MAJOR MOUNTAIN RANGES: Rockies, Coast, LaurentianMAJOR RIVERS: St. Lawrence, Mackenzie

Map of Canada

NATURE

Canada's remote north and extensive forests are home to wildlife, from bears, wolves, beavers, deer, mountain lions, and bighorn sheep to smaller animals like raccoons, otters, and rabbits. The country's lakes and rivers, which contain about 20 percent of all fresh water on Earth, are full of fish such as trout and salmon.

 

Canada's prairies in the south are home to bison and pronghorn antelope. Farther north are Canada's sprawling evergreen forests, which have lots of wildlife, including moose and black bears. Even farther north is the cold, bare tundra, where herds of caribou and musk ox live.

 

Canadians work hard to protect the native wildlife. Canada has 41 national parks and three marine conservation areas. Nevertheless, species like wolves, lynx, and Atlantic fish have been overhunted and overfished.

PEOPLE & CULTURE

In some ways Canada is many nations in one. Descendents of British and French immigrants make up about half the population. They were followed by other European and Asian immigrants. First Nations peoples make up about four percent of the population.

 

Inuit people live mostly in the Northwest Territories and Nunavut. Many Native Canadians live on their traditional lands, but many others have moved to cities across Canada. First Nations artwork is widely recognized and is seen as a symbol of Canadian culture.

Canadian Flag

GEOGRAPHY

Canada is a vast and rugged land. From north to south it spans more than half the Northern Hemisphere. From east to west it stretches almost 4,700 miles (7,560 kilometers) across six time zones. It is the second largest country in the world, but it has only one-half of one percent of the world's population.

 

Canada features black-blue lakes, numerous rivers, majestic western mountains, rolling central plains, and forested eastern valleys. The Canadian Shield, a hilly region of lakes and swamps, stretches across northern Canada and has some of the oldest rocks on Earth.

 

Canada's far north lies in the frozen grip of the Arctic, where ice, snow, and glaciers dominate the landscape. Few trees grow here, and farming is not practical. Native Canadians, called First Nations people, live in this region by hunting and fishing.

Canadian Dollar,

Photograph by Peter Spirer, Dreamstime

GOVERNMENT & ECONOMY

The British monarch is the head of state of Canada. The monarch is represented by a governor-general, who has very limited powers. Laws are made by Canada's elected federal government, which includes a parliament and a prime minister.

Britain's Quebec Act of 1774 granted Quebec its own legal and religious rights. Despite this concession, many Quebec citizens have long sought independence. In votes held in 1980 and 1995, Quebec decided to stay in Canada. But the second vote was very close, and the debate is still alive.

Canada has provided fish, furs, and other natural resources to the world since the 1500s. Today, it is a world leader in agricultural production, telecommunications, and energy technologies. The vast majority of Canada's exports go to the United States.

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HISTORY

The first people to come to Canada arrived between 15,000 and 30,000 years ago across a land bridge that joined Asia and North America. Around A.D. 1000, the Viking explorer Leif Eriksson reached Newfoundland, Canada. He tried to establish a settlement, but it didn't last.

 

In the 16th century, French and British settlers arrived. Land disputes between farmers and fur traders led to four wars between 1689 and 1763. The final war, called the French and Indian War, left the British in control of Canada, but French influence remains strong even today.

 

In 1867, Ontario, Quebec, Nova Scotia, and New Brunswick combined to form a dominion with its own government, parliament, and prime minister. Manitoba joined soon after. In 1931, Canada became an independent nation.

MathA fraction is part of an entire object.

14 One fourth is yellow

24 Two fourths are yellow.

One half is yellow.

34

Three fourths are yellow.

44 Four fourths are yellow.

Adding Fractions with the Same Denominator

Fractions consist of two numbers. The top number is called the numerator. The bottom number is called the denominator.

        numerator         denominator

To add two fractions with the same denominator, add the numerators and place that sum over the common denominator.

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1/3, 4/3, 11/3

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♫ "Multiplying fractions no big problem,Top times top over bottom times bottom,

"Dividing fraction, as easy as pie,Flip the second fraction, then multiply,

"If adding or subtracting is your aim,The bottom numbers must be the same!

"Change the bottom using multiply or

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divide,But the same to the top must be applied,

"And don't forget to simplify,Before it's time to say goodbye"

♫

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