Part 3: Water hyacinths

Questions 21-22
Choose TWO letters, A–E.

Which two problems are caused by water hyacinth?

A plants and fish are poisoned
B farmers cannot fish
C the dam’s structure is damaged
D electricity production is affected
E electricity production is affected

 

Questions 23-26
Choose the correct letter, A, B or C.

  1. Where was water hyacinth originally from?
    A Latin America
    B Africa
    C Europe
  2. What is the primary cause of the decrease in nutrients from the soil?
    A soil erosion
    B a change of rainfall
    C loss of trees
  3. When will the biological solution bring risks to the environment?
    A immediately
    B 6 months later
    C many years later
  4. What does John say about the mechanical solution?
    A ineffective
    B dangerous
    C expensive

 

Questions 27-30
What is the benefit of the cut-down water hyacinth to each of the following aspects? Choose FOUR answers from the box and write the correct letter, A–F next to Questions 27–30.

Benefits of the cut-down water hyacinth
A can reduce the effect of global warming
B can be used as an alternative energy resource
C can make quick profits
D can produce materials for plants to grow in
E can be good for human health
F can produce fertilizer

  1. dried water hyacinth – ……………
  2. mushroom farmers – ……………
  3. oyster and straw mushrooms – ……………
  4. cows – ……………

 

Keys

Section 3
21 – B
22 – E
23 – A
24 – C
25 – C
26 – C
27 – D
28 – C
29 – E
30 – B

 

Transcript

 

Jon, how is it going with your research on water hyacinths?

Well, I went on a field trip on my own and collected the primary data. After I came back, I also referred to the published data.

So, what do you know about this plant?

The water hyacinth grows in tropical countries. It has beautiful purple-blue flowers, but everybody hates it.

Why is that?

Water hyacinth, as the world’s worst invasive aquatic plant, has attracted significant