Past Simple and Present Perfect

Past Simple versus Present Perfect
Past Simple	Present Perfect
complete action which happened at a time in the past:   e.g. She left yesterday. (When did she leave? Yesterday.)	complete action which happened at a time in the past e.g. Don has left for Madrid. (We don't know when he left; unstated time; he's now there or on his way there.)
past action which is and happened at a definite past time not mentioned e.g. I met John Lennon. (I won't meet him again; he's dead. – period of time finished)	past action which is and happened at a definite past time not mentioned   e.g. I' ve spoken to Richard Gere. (I may speak to him again; he's alive. – period of time not finished yet)

10.1 Read the text about climate change. Choose the correct form, A or B, to complete the sentence:

At the moment, scientists agree that the world's climate 1) B warmer over the past 50 years, but they disagree about the causes. Some believe that human activities 2) ___ climate change. They argue that for 1,000 or 2,000 years before 1850, when records3) ___, the temperature was more or less stable. Short warm or cold periods 4) ___ during that time, but the climate always5) ___ to the same level. However, since the Industrial Revolution, human beings 6) ___ more and more fossil fuels, such as coal and oil. In 1800 the atmosphere 7) ___ around 280 parts per million of carbon dioxide (CO2). Since then there 8) ___ an increase of about 3 l%. This extra carbon dioxide 9) ___ the world's temperature because of the greenhouse effect.

Other scientists disagree that human activities over the past 50 years 10) ___ global warming. They point out that volcanoes and other
natural processes 11) ___ CO2 into the atmosphere, and that human activity12) ___ a rise in CO2 of only three per cent.

In 1999, 156 countries13) ___ the Kyoto protocol, part of a United Nations agreement on climate change, which14) ___ into force in 2005.They 15) ___ to reduce their emissions of CO2 and other greenhouse gases, although so far, some countries, such as the USA and
Australia,16) ___ any action.

1. A became B has become

2. A caused B have caused

3. A began B have begun

4. A occurred B have occurred

5. A returned B has returned

6. A burned B have burned

7. A contained B has contained

8. A was B has been

9. A raised B has raised

10. A caused B have caused

11. A always released B have always released

12. A contributed B has contributed

13. A signed B have signed

14. A came B has come

15. A agreed B have agreed

16. A did not take B have not taken

Present Perfect Continuous

Use

1) actions started in the past and continuing up to the present

He 's been writing a letter for two hours. (He started two hours ago and he's still writing it)

2) past actions of certain duration having visible results or effects in the present

She 's been crying. (Her eyes are red.)

3) actions expressing anger, irritation, annoyance, explanation or criticism

Who has been using my toothbrush? (annoyance)

4) emphasis on duration (usually with for, since or how long) She 's been calling on clients since this morning.

Time expressions: how long, for, since

Note: live, feel and work can be used either in the Present Perfect or the Present Perfect Cont. with no difference in meaning.

I’ve been living / I’ve livedin Rome for a year.

11.1 Complete the sentence using the verb in brackets in the present perfect continuous form:

1. I’m sorry to keep you waiting. I hope you (not wait) __________ long.

2. There you are! We (look for) __________ you all morning!

3. I feel really tired. I (study) __________ hard lately.

4. Anna has got a really good suntan. She (go) __________ to the beach a lot.

5. Tom needs cheering up. He (have) __________ a lot of problems lately.

6. I haven’t seen you for ages. What (you / do) __________?

7. I (work) __________ here for the past three years, and I really like it.

8. Sam and Chris (paint) __________ their room, and their clothes are covered in paint!

11.2* Underline the correct form:

A. Scientists 1) have recently identified / have been identifying a new species of animal in the rainforest of Borneo. They2) have been searching / searched for this creature for several years, after reports from local villagers, and say it is a type of lemur.

B. Archaeologists in Guatemala 3) have found / have been finding a Mayan wall painting which they think is more than 2,000 years old. Archaeologist William Saturno 4) explored / has been exploring the site since 2002.

C. Scientists using the Hubble Space Telescope think they5) found / have found two new moons circling the planet Pluto. Astronomers6) have been looking / looked closely at Pluto since 1978 when they 7) spotted / have spotted its first moon. The telescope8) worked / has been working for fifteen years, and 9) has been producing / has produced more than 700,000 images of the universe.

D. Australian scientists10) have been discovering / have discovered a new coral reef over 60 km long in the Gulf of Carpentaria by using satellites to spot the reefs in deep water. Recently divers11) have managed / have been managing to reach the reefs and take photographs.

Past Continuous

Use

1) action in the middle of happening at a stated past time

He was playing tennis at 4.30 yesterday.

2) past action in progress interrupted by another past action. The longer action is in the Past Continuous, the shorter action is in the Past Simple.

While I was get­ting dressed the bell rang.

3) two or more simultaneous past actions

While I was sunbathing, Tim was swimming.

or background description to events in a story

She was flying to Paris. The sun was shining...

Time expressions: while, when, as etc

12.1* Underline the correct form:

1. While he took / was taking a bath, Archimedes discovered / was discovering the principles of density and buoyancy.

2. When Edouard Benedictus, a French scientist, worked / was working in his laboratory, he dropped / was dropping a glass bottle which had some plastic inside – and invented / was inventing safety glass.

3. Columbus arrived / was arriving in America while he tried / was trying to reach the Far East.

4. Alexander Fleming discovered / was discovering penicillin by accident while he looked / was looking at some old experiments.

5. While Hiram Bingham climbed / was climbing in the mountains of Peru in 1911, he discovered / was discovering the lost city of Macchu Picchu.

6. While Isaac Newton sat / was sitting under an apple tree, an apple fell / was falling on hishead, and he understood / was understanding gravity.

7. While Dr Harry Coover tried / was trying to invent a newkind of plastic, he made / was making a very softsubstance which stuck / was sticking things together. It was Superglue.

8. While he observed / was observing the Moon throughhis telescope, Galileo realized / was realizing that it hadmountains and craters.

12.2* Complete the sentence with the past simple or past continuous form of the verb in brackets:

Alexander the Great

While he 1) (grow up) was growing up, the philosopher Aristotle was his teacher. Alexander 2) (become) _______ interested in science, medicine, philosophy and literature. While his father Philip 3) (attend) _______ his daughter's wedding, a young nobleman 4) (murder) _______ him. Alexander was king of Macedonia at the age of 20.

While he 5) (fight) _______ his enemies in the north, the Greeks in the south 6) (start) _______ a rebellion. He 7) (destroy) _______ all their cities. He 8) (lead) _______ his army against the Persian Empire through what is now Turkey 9) (stay) _______ in the ancient city of Gordium, he 10) (undo) _______ the Gordian knot. A legend said that only a future king of Asia could do this.

While his army 11) (march) _______ through Persia, it 12) (defeat) _______ Darius, the king of Persia. He 13) (found) _______ the city of Alexandria at the mouth of the Nile while he 14) (visit) _______ Egypt. While he 15 (travel) _______ with his army, he 16) (give) _______ his name to many other towns.

He 17) (kill) _______ his friend Clitus in a quarrel, while they 18) (have) _______ dinner.

While he 19) (attack) _______ the city of Mali in India, he 20) (receive) _______ a serious wound from an arrow.

While he 21) (attend) _______ a banquet in Babylon in 323 BC, he 22) (fall) _______ ill and 23) (die) _______.

The Vikings in America

According to Viking records, around the year 1000, while some Viking sailors 1) (look for) were looking for the coast of Greenland, they2)(reach) _______ the eastern coast of America. While they 3) (live) _______ there, they 4) (try) _______ to trade with the local Native Americans, known by the Vikings as Skraelings, but in the end the Native Americans 5) (fight) _______ them and 6) (drive) _______ them out. After several attempts to return, the Vikings 7) (give up) _______. In 1968, while some archaeologists8)(work) _______ inNewfoundland, they9)(discover) _______ the remains of one of the Viking settlements, and 10) (prove) _______ that this story was true.

Charles-Marie de la Condamine

In 1735 Charles-Marie de la Condamine1)(sail) _______ to South America. At that time, scientists 2) (argue) _______ about the shape of the Earth. The French Academy 3) (want) _______ him to take measurements on the Equator, along with two other scientists. The work 4) (take) _______ them eight years and in the end, another scientific team5)(find) _______ the answer they 6) (look for) _______. While de la Condamine7)(travel) _______ home along the River Amazon, he8)(learn) _______ many interesting things about the local people and their way of life. When he9)(arrive) _______ in Paris in 1745, he 10) (receive) _______ a hero's welcome.

Past Perfect

Use

1) past action which occurred before another action or before a stated past time

He had left by the time I got there. (or by 8.15)

2) complete past action which had visible results in the past

She was sad because she had failed the test

3) the Past Perfect is the past equivalent of the Present Perfect

(He can't find his watch He has lost it) He couldn't find his watch. He had lost it

Time expressions: for, since, already, after, just, never, yet, before, by, by the time etc.

13.1* Read the following Information about famous moments in history. Then underline the correct form. Only one verb in each paragraph is past perfect:

1) Columbus left Spain in August 1492 with three ships, to try and find a way to India by sailing west instead of east. When his ships1) finally reached / had finally reached land on 12 October, he thought he was there, but the ships2) actually arrived / had actually arrived in America instead.

2) Captain Robert Scott wanted to reach the South Pole first. He and his companions finally arrived there on 1 January 1912 after a terrible journey across the ice, but3) found / had found a Norwegian flag. Unfortunately for Scott, Roald Amundsen 4) got / had got there on 14 December, 18 days earlier.

3) Leonardo painted his famous The Last Supper between 1495 and 1498, but the painting started to deteriorate within 50 years. The most common explanation for this used to be that Leonardo5) used / had used the wrong kind of paint, but experts have always disagreed about this, and many believe that the damp in the wall is the cause of the damage. Between 1978 and 1999, experts6) restored / had restored the painting, and the public can now see it again.

13.2* Complete the sentence with the past simple or past perfect simple form of the verb in brackets:

1. When I (try) tried to use my laptop, I realized the battery (run) _______ down.

2. I (turn) _______ the computer off, but forgot that I (not save) _______ my work.

3. I only remembered I (not pay) _______ the bill when my Internet connection (stop) _______ working.

4. When I (receive) _______ the e-mail, I couldn't understand who (send) _______ it.

5. When I (check) _______ the instructions, I understood what I (do) _______.

6. I knew I (receive) _______ a virus when I (run) _______ the anti-virus program.

7. As soon as I (download) _______ the document, I knew I (make) _______ a mistake.

8. I could see what (go) _______ wrong as soon as I (look) _______ inside the printer.

9. I knew I (press) _______ the wrong key when nothing (happen) _______.

10. When the screen (go) _______ blank, I couldn't understand how it (happen) _______.

13.3 * Read these sentences about Julius Caesar. Then complete the sentence with the past simple or past perfect form of the verb in brackets:

Julius Caesar 1) (come) came from an aristocratic Roman family, though his family was not rich by Roman standards. When he was 15 his father 2) (die) _______, and to avoid political problems in Rome, Caesar 3) (serve) _______ as a soldier in the east. By the time he 4) (return) _______ to Rome, he 5) (win) _______ awards for bravery. He 6) (become) _______ a member of the Senate, and governor of what is now Spain. By the age of 40 he 7) (rise) _______ to the top of the political world, and 8) (form) _______ a political alliance with a powerful general, Pompey, and a rich man, Crassus. Between 58 BC and 49 BC he 9) (fight) _______ a war against the people of what are now France, Belgium, Switzerland and parts of Germany. By the end of this war, according to the historian Plutarch, three million men 10) (die) _______. In 50 BC the Senate 11) (order) _______ Caesar to return to Rome. By that time, Crassus was dead and Pompey 12) (become) _______ Caesar's enemy. In the civil war that followed, Caesar 13) (defeat) _______ all his enemies. By the time a group of Roman senators 14) (murder) _______ him in 44 BC, he 15) (be) _______ the most powerful man in Rome for only a year.

13.4 * Choose the correct form. A, B or C, to complete the sentences:

On 26 December 2004, Tilly Smith, a 10-year-old British schoolgirl, 1) C on the beach with her family. They 2) ___ Christmas in Thailand. Suddenly Tilly 3) ___ that something was wrong. She could see that the water 4) ___ and waves 5) ___ up the beach. The beach 6) ___ smaller and smaller. She 7) ___ that there had been an earthquake in Sumatra that morning, but she8) ___ a geography lesson she 9) ___ at school just two weeks before. So she 10) ___ her mother what she 11) ___ about earthquakes and giant waves. Luckily for the Smith family, Tilly's teacher Andrew Kearney 12) ___ the class about earthquakes and 13) ___ them a video of a tsunami in Hawaii. Tilly 14) ___ screaming at her parents to get off the beach. They 15) ___ Tilly back to their hotel, which was not too close to the shore, and16) ___ the alarm. One of the staff, who was Japanese,17) ___ the word tsunami, and 18) ___ everyone to leave the beach. From their room on the third floor, the Smiths19) ___ the terrible effects of the tsunami on the area. Thanks to Tilly, everybody from that beach 20) ___ that terrible day.

1. A walked	B had walked	C was walking
2. A spent	B had spent	C were spending
3. A felt	B had felt	C was feeling
4. A rose	B had risen	C was rising
5. A came	B had come	C were coming
6. A got	B had got	C was getting
7. A did not know	B had not known	C was not knowing
8. A suddenly remembered	B had remembered suddenly	C was suddenly remembering
9. A had	B had had	C was having
10. A told	B had told	C was telling
11. A learnt	B had learnt	C was learning
12. A taught	B had taught	C was teaching
13. A showed	B hadshown	C was showing
14. A started	B had started	C was starting
15. A took	B had taken	C were taking
16. A raised	B had raised	C were raising
17. A understood	B had understood	C was understanding
18. A ordered	B had ordered	C was ordering
19. A watched	B had watched	C were watching
20. A survived	B had survived	C was surviving