Road to IELTS Academic Listening Test 5 (Online Test)

Good morning, everyone. Welcome to our visit to one of the most famous caves in Vietnam.

As you know, this cave is famous for its wildlife, and one of the creatures you will observe in here is the small cave cockroach. They live mostly on the bird and bat droppings that are so plentiful in the caves. The guardrails along the trails are covered with these droppings, and this makes a feast for the cockroaches, so be careful where you put your hands. They will not harm you, but it can be a shock if you touch them!

Once you are in one of the main caves, look out for the green centipedes. They will not be on the trail but can often be seen on the wall close by. They feed on other insects and are fascinating to look at because of their colour, and, of course, their many legs. Please, please do not try to pick one up though; these centipedes have a very nasty poisonous bite.

There are also deep red millipedes. These have a fully rounded shape, and they look like a streamlined elongated train with a hundred or so closely packed legs extending right and left.

When you get to the large high caves, you should look right up above you for the swifts and bats. The bats in this cave are mostly a type of dwarf bat, which are common in this part of the world. They will be clustered high up against the walls – maybe a hundred or two hundred together. They look like shadows high on the walls of the cave. They are likely to be very quiet right now, but because there are so many of them together you will have no difficulty identifying them. They sleep all day until they all leave the cave in a massive flock on their nightly hunt for flying insects.

The swifts are the creatures you can see flying around during the day, especially if they have young ones to feed. They can navigate in the darkness here, and will fly outside in ones and twos at dusk to catch small winged insects like mosquitoes. However they tend to return before it is pitch black outside, and they do not hunt at night. The swifts make nests, usually higher up on the ceiling of the cave.

Before you hear the rest of the talk, you have some time to look at questions 16 to 20

Now listen and answer questions 16 to 20.

The paths tend to run around the edges of the large caves. Mostly this is because the centre is a mound of guano – the bird and bat droppings. This is also the source of the strong smell inside the caves. You may not like this smell, but the locals know its economic value. They have harvested the products of these caves for centuries. The guano is very valuable as fertiliser, and so it’s collected each year, once the young birds have grown and the swifts have abandoned their nests.

The guano is not the only valuable by-product of the wildlife here. As you travel through the caves, you will notice some bamboo structures. These very flimsy looking sets of poles that go a full hundred metres, right up to the roof, are what the locals climb up to gather the swift’s nests. These are even more valuable than the guano, as they are the main ingredient in bird’s nest soup.

Before you begin, it’s time for some safety instructions. As you probably know, this is a huge limestone cave that goes about one kilometre back into the hills and in places it’s a hundred metres in height and three hundred metres wide. There is no need to crawl around in here as you do in other caves, but it is dark inside, of course … that’s why I insisted that you bring a working light – please check that it shines brightly, and ensure that you stay together with others who have a good torch. In one of the larger areas of the cave, the roof is pierced so some sunlight will get through. It is best to turn your torches off if you can see well, and save your batteries.

It is a good idea to put your waterproof jacket on now. The walls may be wet but that is not the main reason for the jacket. The bats and birds do excrete, and they are above you, so just in case … and of course, your hat or hood also keeps you safe from animal droppings.

It’s not advisable to use the guardrails as handholds. There are lots of droppings on those rails, and don’t forget the cockroaches!

You absolutely must follow the marked trails. The guardrails on either side are put there so that you cannot mistake them. We take no responsibility for your safety if you go over or under the rails into other cave areas.

Keep your torches shining on the path whenever you are moving, just to be sure of your footing, and don’t try to go too fast. You might trip, and you will certainly miss some of the fascinating wildlife in the cave.

Now it’s time to begin the tour …

That is the end of section 2. You now have half a minute to check your answers.

Now turn to section 3.

STUDENT: Hello, Mr Hadstone. Is this the right time for our meeting?

TUTOR: Yes, it is. Thanks for coming in at such a late hour, Mary. I know you’ve had a busy day studying and will be keen to get home … and thanks for volunteering to run this project. It’s going to help you develop and practise skills needed by teachers today. Field trips are getting more and more a part of school life, so as a student of education it’ll be wonderful training for you. It’s really a great opportunity.

STUDENT: We did loads of field trips at school, so I’ve got a good idea of what sort of things we could do.

TUTOR: Hmm, I expect so, but we’re here to go through the basics of planning one, and the trip leader carries a load of responsibility. Right now, you’re focusing on activities, but your main job is to consider the dangers, and come up with ways of countering or avoiding them. There are lots of government regulations you won’t have been aware of on your school trips, but they are just a guideline for your own planning….some of those school trips you went on would have been pretty adventurous, right?

STUDENT: Yeah.

TUTOR: OK, and your plan needs to be tailored to the kind of trip you’re doing. On a well-planned and successfully led adventure trip, we don’t often hear of problems … even though sometimes there’s bad weather, for example, that a school party has managed to combat. That’s because the leader created a well thought out hazard management plan.

STUDENT: Oh, I thought I’d just be taking my mates out on a trek – now it’s all paperwork!

TUTOR: Yes, well, that’s why I called you in. We’ll work on this together over the next few days – I just wanted to give you a heads-up on what you’ll need to think about. There are some aspects that every trip needs to consider. What do you think they might be?

STUDENT: Uh ... well …heavy rain, or high winds, I guess, and any dangers in the terrain...

TUTOR: Yes, we call those the significant factors … and another important one is the make-up of your group. But, you don’t need to go overboard. There are some kinds of hazard you won’t need to think about at all: things like hurricanes, earthquakes, radioactivity, or major diseases such as cancer. The official name for those is unlikely events, because they almost certainly won’t happen.

Before you hear the rest of the conversation, you have some time to look at questions 26 to 30.

Now listen and answer questions 26 to 30.

TUTOR: OK, so let’s consider the hazards seen as most likely on a field trip into the countryside. Weather causes real problems – overexposure to the sun or the cold – even the wind can have a big impact. And, of course, the weather can change very suddenly and without warning.

STUDENT: Yes, people can get into trouble in the hills if they don’t bring extra layers of clothes and a jacket – even if they start walking on a hot day. Oh … and a raincoat, too, of course. Umm …what’s next then?

TUTOR: Well, let’s think about possible activities and what you might need.

STUDENT: Yes, OK … Well, for hiking of course we need a first aid kit. Oh … and a decent topographic map of the area. And we need to make sure that more than one person can read it. I’ve run into lots of difficulties in the past with people who can’t identify even major features, like rivers. And some people have no idea about contour lines. Ah….and I suppose a compass, too.

TUTOR: You’d need to list those. Then there are things that may be obvious, but must be written down and considered seriously. For example, if there’s a possibility of falling more than 2.5 meters, that’s considered life threatening, and I’m sure you would be aware of problems near the sea, like tides or high waves – and the trouble you can get into where there’s a possibility of an avalanche or a mudslide … or a flash flood, if you’re anywhere near rivers.

STUDENT: Yes, well, I was thinking of an adventurous route for this trip … you know, that’s always more fun, and it’s such a cool feeling when you’ve achieved something really difficult.

TUTOR: Yes, OK, but then you need to consider who’s going to be in your party…. don’t go and plan things that are beyond the reach of most people, or you’re asking for trouble. You need to take into account the physical strength and experience of the party as a whole. When you make your groups, make sure there’s at least one person in each one who’s been hiking a few times before.

STUDENT: Wow, there’s a lot to write down, isn’t there? I’m really keen to get started now.

TUTOR: Well, good, because there’s a lot more detail to consider. For now, I’ll just mention two more of the common hazards for high school trips, in particular.

STUDENT: Yes?

TUTOR: The Ministry of Education website says – don’t use inexperienced volunteers, and don’t allow student drivers to bring their own cars, or to drive anyone else’s car, for that matter.

STUDENT: Well … now I really have something to think about! Thanks, Mr Hadstone.

That is the end of section 3. You now have half a minute to check your answers.

Now turn to section 4.

The topic for today’s lecture is cochlear implants, which are a relatively new form of technology for assisting people who are profoundly deaf.

First, let’s revise how normal hearing works. If you look at image 1, you will remember that the ear has three sections. The outer ear, or pinna, picks up sounds, which are then channelled through the ear canal to the eardrum, where they are transformed into mechanical vibrations. These are sent to the cochlea, or inner ear. Inside this snail-shaped tube, there are sensory hearing cells that have a variety of functions. The outer hair cells make soft sounds louder, and reduce the volume of louder sounds. The inner ear cells transfer this information to the auditory nerve, and thence to the brain, which interprets the input as sounds. This sophisticated and sensitive process allows us to process a huge variety of auditory input. For those who are profoundly deaf, the system functions poorly or not at all, and the brain does not receive the input it needs to process and interpret sounds.

Image 2 shows how a cochlear implant works. You can see that the implant has three main parts. The first, external part, behind the ear itself, is the microphone and, at the back of this, you can see its associated speech processor, which is a tiny computer. This analyses and digitises sounds and sends them to the transmitter, which is worn on the head. Those sounds need to be converted into electrical impulses so that they can be sent to the cochlea. If you look carefully at the image, you can see that just under the skin, directly behind the transmitter, is a surgically-implanted receiver. This receives the sounds from the transmitter. It converts these sounds into electrical impulses, which are sent directly to an electrode array that is implanted inside the cochlea itself, thus completely bypassing the ear canal.

As you have seen, a cochlear implant does not operate in the same way as the ear, nor, in fact, as a hearing aid. In cases of mild hearing loss, hearing aids can be very helpful. They simply amplify the normal sound waves as they travel down the ear canal. However, they generally cannot overcome severe hearing difficulties, and this is where cochlear implants come into play. So, what are the pros and cons of using a cochlear implant?

Well, firstly, cochlear implants can deliver significant improvements in hearing for some users, and some people report dramatic improvements in the perception of individual words and sentences over the weeks and months after an implant. However a cochlear implant is not a magic bullet that works equally well for all users. The sound signals that the brain receives from an implant are quite different from normal ones, and this means that the user has to relearn how to hear. Many users report that speech sounds robotic after a cochlear implant, and the degree to which people can adjust to this new kind of hearing varies hugely with each user and situation.

It is important to understand that a cochlear implant is not a cure for deafness, and that the user is still deaf. Especially for a child, an implant is a long-term commitment, involving lengthy and intensive training. The user must learn to reinterpret sounds, and will likely need to augment this with speech therapy, so that people in the community can easily communicate with them. The implants work much better in quiet situations than in noisy ones, so they still need to learn to lip-read and to use sign language. The surgery itself is not without risk, though it has greatly improved since it was first performed, and there is some possibility of damage to facial nerves. Another disadvantage of a cochlear implant, is that the surgery may remove any natural hearing that the deaf person still retains. This takes away the possibility of using a hearing aid should the implant not be effective. For this reason, many users have implant surgery performed on only one ear, the one with the least natural hearing.

So, who is best suited to receiving an implant? Many factors impact on this decision. The most significant one appears to be the duration of the deafness, and, as you would expect, those who have been deaf for a long time generally have lower success rates. The second, related factor is how old the patient was when they became deaf, and maybe more significantly, whether they had learned to speak before they became deaf. Those who become deaf post-lingually generally have better outcomes. Another factor is the health and structure of the cochlea, and how many nerve cells the user retains. This is related to the cause of the hearing loss, and recent research is exploring how the spiral ganglion, or nerve cells are affected by disease. OK, let’s now move on to discuss the long-term prognosis for …

That is the end of section 4. You now have half a minute to check your answers.

That is the end of the listening test.