You will hear a lecturer giving a presentation about the history of coffee.
First, you have some time to look at questions 31 to 40.
Now listen carefully and answer questions 31 to 40.
In this talk, I'll consider coffee and the role it has played in both economic and social life.
It is generally believed that people first drank it in the Arab world.
Written records before the 16th century are extremely scarce, although that does not prove that coffee was unknown earlier.
There is evidence that people initially collected coffee from wild bushes in Ethiopia in northeastern Africa.
Early in the 16th century, traders began buying it, and the drink slowly spread across the Middle East.
We also know that in 1522, in Constantinople, the heart of the Ottoman Empire, the court doctor authorized coffee as a medicine.
By the middle of the century, coffee plants were being cultivated in Yemen.
For roughly the next hundred years, that region supplied most of the coffee consumed in Africa and the Arab world.
One striking feature of coffee is the way it influenced social life.
People seldom drank it at home.
Instead, they visited coffee houses where men in particular met to drink and exchange views about current affairs.
Authorities considered these discussions potentially threatening.
In 1623, Constantinople's ruler therefore ordered the destruction of every coffee house in the city.
New establishments opened after he died, however, and coffee drinking continued.
During the 17th century, the habit reached Europe.
Coffee shops there also became meeting places where ordinary people, usually men, gathered to exchange ideas.
Some observers consequently compared their function with that of universities.
By bringing people together outside their homes to discuss the major issues of the day, the shops had a powerful influence on society.
Numerous social movements and political changes began in coffee house conversations.
Toward the end of the 17th century, Yemen lost its control over production.
Coffee cultivation then expanded worldwide, assisted by European colonization.
European powers created plantations in Indonesia and the Caribbean, and output from their colonies rose rapidly.
Coffees produced in different locations often took names such as mocha or java from the port through which they were exported to Europe.
Labor arrangements, though, varied considerably between colonies.
In Brazil and a number of Caribbean colonies, coffee grew on enormous plantations worked mainly by slaves.
Java followed another pattern.
After the Dutch colonized the island, local farmers cultivated coffee and handed a proportion of the crop to the colonial authorities, so the beans served as a form of taxation.
Regardless of the system, 18th century European rule tied coffee production closely to colonization.
Growers produced ever larger quantities to satisfy European demand, and coffee became almost as important as sugar, which was cultivated under very similar conditions.
Even so, prices remained too high for most people to drink coffee regularly at home.
Consumption still centered on public coffee houses, and the drink retained an element of luxury.
In Britain, meanwhile, tea arrived from China and gradually displaced coffee.
It was initially affordable only to the wealthy, but by the late 18th century it was consumed widely.
The United States, having gained independence from Britain in 1776, did not make the same change to tea.
Coffee remained its preferred drink, as it is today.
By the start of the 19th century, coffee was already produced and consumed on a large scale.
During that century, however, output surged and prices fell.
One reason was the development of cheaper, more efficient transportation.
Coffee then became affordable to workers rather than remaining a middle-class drink.
This coincided with industrialization across much of Europe.
Factory work sometimes continued after dark, requiring employees to work through the night.
Coffee's stimulating effect therefore became valuable.
It was no longer simply a breakfast drink.
There were also developments in cultivation.
