IELTS Recent Actual Test 1 Academic Listening Test 2

Continuing our broadcast of public service announcements, Worldwide Helpers announces upcoming vacancies for a number of volunteer worker positions. All applicants must meet the following requirements.
First of all, applicants must be over 18 years of age. The company apologises, but there can be no exceptions to this rule. Second, persons interested in these positions may not have police records. Minor traffic offences like a parking ticket are, of course, no problem. But, and I quote, "past and present drug users and sex offenders" need not apply. The employer will, of course, check with the police to verify your clean record.
In addition, applicants must supply references from past or present employers or teachers along with their recent CV. These references must testify as to the applicant's work habits and/or character. Remember, these are references from employers or teachers. A note from your dear old Mum won't do. Worldwide Helpers assures me that they will contact these references to confirm they are genuine.
Although all positions are volunteer, the employer will reimburse some of your expenses. For example, they will pay for transportation to and from the job site. Aside from that, the cost of phone calls is covered.
As for the positions themselves, there are three types. The first involves assisting persons confined to wheelchairs. For this position, volunteers must be physically fit and in excellent health. They must be able to lift at least 150 pounds. They should also have a current First Aid certificate from the Red Cross. But the most important requirement is that the volunteer must have his own car. On Tuesday afternoons, the volunteers take their clients to various scenic spots around the city to experience and enjoy nature.
If you don't drive, but you'd still like to get involved, the centre has a number of openings for people to read to the blind. Readers must, of course, read English clearly. Persons with no foreign accent are preferred. For these positions, you must be available on Monday mornings. Oh, wait, I see a note here. There is one opening for someone who can read Urdu. Apparently, there is a Pakistani blind person who'd like to hear his or her native language. But the other positions are all in English.
And finally, there are a limited number of volunteers needed to care for disabled children. I'm sorry, but the information I've been given does not say how many children or what disabilities they have. In any case, you are needed to care for the children for one week in August. Apparently, this will be at the close of the summer holiday. I would guess this involves helping them with the routine chores of daily life. Again, volunteers for this position must know basic First Aid, be in good health, and be able to lift up to 75 pounds.
All applications for this position have to be submitted no later than Monday, August 8th. Applications may be made either by regular postal service - the "snail mail" - or by e-mail. The mailing address is Worldwide Helpers, Post Office Box 651, East Surrey BY8 99C. Please write "ATTENTION: Mary Smith" on the envelope. Or you can send e-mail to acrawfor@worldwidehelpers.org. That's A-C-R-A-W-F-O-R at W-O-R-L-D-W-I-D-E-H-E-L-P-E-R-S dot org. So get out there and do something good!
OK, our next announcement is looking for someone to "facilitate" tiger breeding at the London Zoo. And, get this, it's a "strictly volunteer" position. That means you don't get paid! Oh my God... I'm sorry ladies and gentlemen, but I just have to laugh...

DAVE: Are you just leaving the library now? I saw you get there at 8:00 a.m.!
PETE: Yeah, I've been there all day.
DAVE: What for? They hired a cute new librarian or something?
PETE: I wish. No, it's the presentation that I will give in Environmental Science the day after tomorrow.
DAVE: What's it about? I heard you were really excited about the class. And Dr Schnee also calls you for the "arcane" questions, as he calls them.
PETE: It's about environmental damage in the Yucatan.
DAVE: Excuse me, what? Or is that where?
PETE: Yucatan. It's a state in Southeast Mexico.
DAVE: So what's happening there?
PETE: Agriculture is having a really adverse impact on the environment. There are too many farmers doing too much farming. It's really destroying the forests and ruining the soil. Deforestation is a major problem there now.
DAVE: How did you learn about this? I don't recall Dr Schnee saying anything about it in lecture.
PETE: Yes, but my brother went there last month, you know, to look at the old cities the Maya Indians built. That's what first got me interested.
DAVE: Your brother Tom?
PETE: No, Dick, Harry's twin. Anyway, he told me how few trees there were now and how much empty ground that grows almost nothing. He said the place looked more like the desert than jungle in some parts. It brought environmental damage. So I started looking for materials in the library. Here, look at this magazine.
DAVE: What's in it?
PETE: It's an old issue of "National Geographic". It includes interviews with tourists who've been there in the past few years. It's pretty bad. See the photos?
DAVE: I see the photos, but one or two photos don't prove anything.
PETE: Then read what the article says. Right there. The first thing it points out is how soil samples show it is hard for anything to grow there. It says how an area of 21,000 square kilometres has lost most of its forest in the past ten years. See, there are graphs. As the number of farmers increases, the acres of forest have decreased. It's an inverse relation.
DAVE: So how big is that state? I'm sorry, but I've never really learned the metric system.
PETE: It's bigger than the state of Massachusetts!
DAVE: That's shocking! Anything else?
PETE: There's lots of else. Scientists say there's a "growing area" of about 10.5 square kilometres where nothing can grow at all. It's like the beginning of a desert.
DAVE: Oh yes. What Dr Schnee called "desertification". But, why can't anything grow there? I've never really studied soil chemistry.
PETE: I'm just starting to look into that subject, but my sister Marie is a geologist and she says the problem is that the soil has too much saline, with no plants helping to adjust the chemistry. Apparently, that's a common problem with soil types throughout areas with rainforest. Once you lose the plant cover, it's difficult to bring it back. Reforestation is almost impossible, even if the land is not being used for other purposes.
DAVE: Wait a minute. What is "saline"?
PETE: Saline is salt dissolved in water. Scientists who've gone there have taken measurements. They do this by gathering a sample of the soil and running a simple test that shows the ionisation of the solution. The Geology Department in our own university has reviewed the soil at the site, too. They're right. It looks pretty bad. The level of salinity is going up. But the plants that would solve that problem can't be planted in soil like that. There is a narrow spectrum of salinity in which the plants will grow.
DAVE: And once you pass the threshold, there is no way to put the problem right?
PETE: Exactly. It's possible that no one can do anything to stop the trend now. All because of human greed! I...
DAVE: Wait a second. How do you know these "scientists" can be trusted? What kind of reputation do they have? Are they reliable?
PETE: Oh they're definitely reliable. They include four members of the faculty from the Geology Department right here at MIT. Here, study these photographs and check the damage yourself. That's what Dr Horst who wrote this book here did. He's newly appointed, but Dr Schnee says he's brilliant.
DAVE: So, where are you going now?
PETE: I'm headed over to the Geography Department to borrow a map for my presentation. You know, this whole problem could have been avoided! The farmers there in the Yucatan...
DAVE: Uh, Pete??
PETE: What?
DAVE: Go take a break! Leave some studying for the rest of us.

Good afternoon, and welcome to Insect Biology 101. I'd like to begin this course with a few remarks about good insects and bad ones. Bugs are all around us and that's both a benefit and an annoyance - sometimes maybe even serious harm. First, let's talk about the good things that insects do for us.
Probably the most important insect for humans, and maybe for all other life, is the bee. Bees help plants in the process of pollination, and thus are necessary to most flowers and fruit-producing trees. That is, they carry pollen from "male" flowers to "female". If it weren't for bees, we'd have very few food plants and no fruit either. In fact, there would be no "we". No less a thinker than Albert Einstein pointed out that, without bees, humanity would be dead within a year or less. We'd starve. It's that simple. That should maybe make us just a little humble.
A little less dramatic is the fact that bees also make the honey we eat. Moreover, they produce beeswax, which is useful in candles and it's also used as a first-rate furniture polish. Sure, these may not be vital to our lives, but they can serve as reminders of how important bees are. That's a point I keep coming back to in this course. Though, in all fairness, I should point out that butterflies aid in pollination as well as bees.
Now, here in Michigan, what's the worst part of summer? Yep, that's right - mosquitoes. But I'm talking about helpful insects, right? So let's look at the dragonfly first. If there were no dragonflies, there would be even more mosquitoes! Dragonflies mainly eat mosquitoes and also a few other insects. Yes, that's right. They don't just fly around, and they also help to eliminate harmful insects. So, the next time you see a dragonfly, don't you dare kill it!
Now let's talk a little about those harmful insects. Take the mosquitoes I just mentioned as an example. Not so many years ago, mosquitoes here in America weren't just annoying. Some were even deadly. They carried malaria and yellow fever. My own ancestor, the Confederate General John Bell Hood, lived through the worst battles of Civil War only to die at age thirty-eight from yellow fever. A pest, not a bullet!
Well, besides the mosquitoes, in summer there is also a kind of insect that never seems tired. Right, that is the fly. Before I go on talking, I must mention an African fly called the Tsetse fly, which feeds on blood and can cause serious diseases in the people and animals that it bites. Besides, it is still a bearer of sleeping sickness, which affects around 300,000 people every year in Africa and can be treated only with toxic drugs that are hard to administer. Worse still, the drugs sometimes don't work.
Other insects, of course, destroy food crops. In China, for instance, locusts continue to be a danger to the harvest in some areas. Less important, but still annoying, moths eat people's clothes and dust mites slowly destroy carpets. Worse, but still in the home, termites or "white ants" eat wood - the wood of your house. If they are not stopped, they can eventually destroy the whole building. Usually they seriously damage a building before anyone even notices them. So, as we all know, insects can be a real trouble.
For some decades in the West, to kill insects with chemicals seemed a good remedy. Unfortunately, chemicals can only be used in a limited area for a limited time. It's a small-scale solution. The insects come back. Worse still, some of the poisons used like DDT were found harmful to the environment. Many kinds of wildlife, like hawks, were harmed. And people in chemical-using rural areas have one of the highest rates of liver cancer in the world. It's no secret that the chemicals remain harmful to humans.
Like all species, insects adapt to their changing environments at an amazing rate. When a new chemical is introduced to their habitat, the insects that survive are generally the ones with some way of resisting the harmful effects. They then breed with the other survivors, and just like that insects become resistant to most poison in a few generations. An insect generation, remember, is a couple of months at most!
So, again we have to ask: what to do? Well, there are biological solutions. Some of these are pretty simple. One is destroying the insects' habitat. You take away their home or food. Cleaning your kitchen is the best way to prevent roaches. No garbage: no food. Getting rid of marshes and swamps eliminates mosquitoes. Other solutions might include bringing in dragonflies or bats in areas where mosquitoes are many. This is a cheaper alternative to chemicals. Biological methods like this also bring no extra pollution to the environment. But you have to be careful. If you change the environment too much, you might be hurting other forms of life accidentally.
One recent method of controlling insect populations involves interrupting their breeding cycle. What does that mean? It means "birth control for bugs". Insects are provided with food that makes them unable to reproduce. Since they can't have babies, the population disappears, or nearly so. And since no young are born, resistance is not a problem with no young insects developing increased resistance. Interrupt the life cycle, eliminate the bug! It's clear that we must have an understanding of the life cycle of the insect. At least, that's the plan. We'll go into more details as this course goes along. Now I will stop here to see whether you have any questions or not.