UNIT 4. IRRIGATION AND DRAINAGE. ACTIVITIES

QUESTIONS

1.-How can you define “irrigation”?

2.-How can you define “drainage”?

3.-Why are irrigation and drainage important in agriculture?

4.-How can we classify water supplies?

5.-Where do water supplies come from?

6.-What surface sources of water can you name?

7.-What subsurface sources of water can you name?

8.-What must we consider before planning a water supply?

9.-Why is silt content important when planning a water supply?

10.-How can we obtain water from an aquifer?

11.-When and where is it possible to use dew to irrigate land?

12.-Why is sewage used for irrigation?

13.-How is water transported from reservoirs and wells?

14.-What is the difference between flood and forrow irrigation?

15.-What do you call the devices that apply water in the form of a mist?

16.-What factors are important when planning a drainage system?

17.-How can we remove the excess of water from the surface of the soil?

18.-How can we remove the excess of groundwater?

CORRECT THESE FALSE STATEMENTS:

1.-A weir is bigger than a reservoir.  

2.-In a drought we have a lot of rain.  

3.-If the salt concentration in water is high, crops will benefit from it. 

4.-In drip irrigation water is applied far from the plant and a big surface of soil is wetted..

5.-Dew and sewage are used for irrigation in very humid regions.

6.-Drainage is easier when the soil has a high percentage of clay-size particles.  

7.-Land with a slope are more difficult to drain.  

8.-If there is a seepage in a pipeline we will collect more water.  

9.-If a plot of land is flooded we must irrigate it.  

10.-Sewage is clean water.  

CONNECTORS

Choose the correct answer:

• 1. Karen is rich; ___, her cousin Kate is poor.
• A. therefore    B. However      C. Otherwise
•  
• 2. You'd better take a taxi. ___, you'll arrive late.
• A. Consequently      B. Furthermore     C. Otherwise
•  
• 3. I enjoy reading this new magazine. ___, it has good articles.
• A. Moreover     B. Nevertheless    C. However
•  
• 4. Jack wasn’t tired.
• A. Otherwise   B. Hence    C. Nevertheless
•  
• 5. Phil was not thirsty; ___, he drank five glasses of water.
• A. however   B. Moreover   C. Furthermore
•  
• 6. The kids didn't study. ___, they failed the course.
• A. Therefore     B. Nonetheless    C. Otherwise
•  
• 7. The weather was terrible. ___, we decided to delay our trip
• A. Furthermore   B. Besides   C. Therefore
•  
• 8. You must buy the tickets; ___, we won't be able to see that play.
• A.  Otherwise      B. Although   C. Besides
•  
• 9. The neighborhood isn't very interesting. I like the house, ___.
• A. Moreover     B. Thus     C. Though
•  
• 10. We live in the same building; ___, we hardly see each other.
• A. However      B. Therefore    C. Furthermore
• 11. _________ my brother worked hard, he failed Maths.  
• A. However      B. Although    C. Furthermore
•  
• 12. The library on 5th Avenue in New York City is one of the best places to do research.  ________________, it has hundreds of the most respected magazines and journals in the world.
• A. However     B. Therefore    C. Besides that
•  
• 13. He likes Sciences and he likes Literature _______________.
• A. as well      B. besides    C. furthermore
•  
• 14. He bought a computer and he _____________ bought a tablet.  
• A. as well      B. also     C. moreover
•  
• 15. Peter is a very intelligent person. _____________, he is very funny.
• A. As well      B. Therefore    C. In addition

INFINITIVE OF PURPOSE

We use the infinite (To + verb) to say why we do something: “He studied hard to pass his exams”. If we want to be more formal we can use “in order to”: “The director sent some cards in order to invite everybody to the party”.

Rephrase these sentences using the infinitive of purpose:

1.-They got up early because they wanted to set off for Madrid.

2.-He is going to the shop because we have run out of sugar.

3.-My sister phoned the travel agency because she is organizing a trip to Malta.

4.-I’m walking fast because I don’t want to be late.

5.-They have gone to the cinema because they want to see a new film.