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Practice your listening comprehension.
Tests that have Listening Comprehension questions:
Canadian Firefighter TOEFL, TOEIC IELTS and CELPIP
Below are practice questions – you can click on the link for an audio file, or print and have someone read the passage to you.
Caterpillars
Butterfly larvae, or caterpillars, consume plant leaves and spend practically all of their time in search of food. Although most caterpillars are herbivorous, a few species eat other insects. Some larvae form mutual associations with ants. They communicate with the ants using vibrations that are transmitted through the soil as well as using chemical signals. The ants provide some degree of protection to the larvae and they in turn gather honeydew secretions.
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1. What do most larvae spend their time doing?
a. Eating
b. Sleeping
c. Communicating with ants.
d. None of the above
2. Are all caterpillars herbivores?
a. Yes
b. No, some eat insects
3. What benefit do larvae get from association with ants?
a. They do not receive any benefit.
b. Ants give them protection.
c. Ants give them food.
d. Ants give them honeydew secretions.
4. Do ants or larvae benefit most from association?
a. Ants benefit most.
b. Larvae benefit most.
c. Both benefit the same.
d. Neither benefits.
Passage 2 – Fire
Fire is the rapid oxidation of a material in the chemical process of combustion, releasing heat, light, and various reaction products. Fire is a rapid oxidization, unlike slower processes such as rust or digestion.
The flame is the visible portion of the fire. If hot enough, the gases may become ionized to produce plasma. Depending on the substances and impurities, the color of the flame and the fire’s intensity varies.
Fire is an important process that affects ecological systems around the globe. The positive effects of fire include stimulating growth and maintaining various ecological systems. Fire has been used by humans for cooking, generating heat, light, signaling, and propulsion. The negative effects of fire include hazard to life and property, atmospheric pollution, and water contamination. If fire removes protective vegetation, heavy rainfall may lead to soil erosion. In addition, when vegetation is burned, the nitrogen it contains is released into the atmosphere, unlike elements such as potassium and phosphorus which remain in the ash and are quickly recycled into the soil. This loss of nitrogen caused by fire produces a long-term reduction in the fertility of the soil, which only recovers slowly as nitrogen is “fixed” from the atmosphere by lightning and by certain plants such as clover.
Fires starts when a flammable or a combustible material, in combination with a sufficient quantity of an oxidizer, such as oxygen gas, is exposed to a source of heat or ambient temperature above the flash point for the fuel/oxidizer mix, and is able to sustain a rate of rapid oxidation that produces a chain reaction. This is commonly called the fire tetrahedron. Fire cannot exist without all of these elements in place, and in the right proportions. For example, a flammable liquid will start burning only if the fuel and oxygen are in the right proportions. Some fuel-oxygen mixes may require a catalyst, a substance that is not consumed, but which enables the reactants to combust more readily.
Once ignited, a chain reaction must take place whereby fires can sustain its own heat by the further release of heat energy in the process of combustion and may propagate, provided there is a continuous supply of an oxidizer and fuel.
If the oxidizer is oxygen from the surrounding air, the presence of a force of gravity, or of some similar force caused by acceleration, is necessary to produce convection, which removes combustion products and brings a supply of oxygen to the fire. Without gravity, a fire rapidly surrounds itself with its own combustion products and non-oxidizing gases from the air, which exclude oxygen and extinguish the fire. Because of this, the risk of fire in a spacecraft is small when it is coasting in inertial flight.[5][6] Of course, this does not apply if oxygen is supplied to the fire by some process other than thermal convection.
Fire can be extinguished by removing any one of the elements of the fire tetrahedron. Consider a natural gas flame, such as from a stovetop burner. The fire can be extinguished by any of the following:
- turning off the gas supply, which removes the fuel source;
- covering the flame completely, which smothers the flame as the combustion both uses the available oxidizer (the oxygen in the air) and displaces it from the area around the flame with CO2;
- application of water, which removes heat from the fire faster than the fire can produce it
- application of a retardant chemical such as Halon to the flame, which retards the chemical reaction itself until the rate of combustion is too slow to maintain the chain reaction.
In contrast, fire is intensified by increasing the overall rate of combustion. Methods to do this include increasing fuel and oxidizer input in this balanced mix, increasing the ambient temperature so the fire’s own heat is better able to sustain combustion, or providing a catalyst; a non-reactant medium in which the fuel and oxidizer can more readily react.
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5. Are oxidation processes like rust the same as fire?
a. Yes
b. No</p>
6. What causes flames to have different colors?
a. The material burning and impurities
b. The material burning
c. Impurities in the surrounding air
d. None of the above.
7. What is one of the positive effects of fire on ecological systems?
a. Fire stimulates grown and maintains some ecological systems
b. There are no beneficial effects on eco-systems
c. Fire can stimulate grown but overall are not beneficial for ecosystems
d. None of the above
8. What happens to potassium and phosphorus when vegetation is burned?
a. Potassium and phosphorus are released into the atmosphere
b. Potassium and phosphorus are not involved in the burning of vegetation
c. Potassium and phosphorus remain in the ash
9. What is necessary for a fire?
a. A combustible material, and an oxidizer
b. A combustible material, and a heat source
c. A combustible material, and an oxidizer and a heat source
10. What is a catalyst?
a. A substance that is produced by the chemical reaction
b. A substance that enhances the chemical reaction
c. A substance that slows down the chemical reaction
d. None of the above
11. How can fire be intensified?
a. Increasing the fuel or oxidizer
b. Lowering the ambient temperature relative to the temperature of the reaction
c. Increasing the fuel and/or the oxidizer
d. None of the above
12. How does applying water to a fire extinguish it?
a. Water increases the CO2 and smothers the fire
b. Water decreases the temperature of the fire, interrupting the chain reaction
c. Water removes the fuel supply
d. Water increases the oxygen available
13. How can a fire be intensified?
a. Lowering the ambient temperature
b. Raising the ambient temperature
c. Decreasing the fuel supply and increasing the ambient temperature
d. None of the above
14. Why are gravity and convection necessary for fire?
a. Gravity is necessary but convection is not necessary
b. Both gravity and convection are necessary to provide a continuous fuel supply and remove un-combusted particles and gases.
c. Both gravity and convection are necessary to prevent a fire from burning out immediately
d. None of the above
Answer Key
Passage 1 – Caterpillar
1. A
Eating. Larvae spend most of their time in search of food and their food is leaves.
2. B
Some caterpillars eat other insects.
3. B
From the passage, the ants provide some degree of protection
4. C
The association is mutual so they both benefit.
5. B
Fire is an oxidation process but is much faster than rust or digestion.
6. A
Depending on the substances, and impurities, the color of the flame and the fire’s intensity will vary.
7. A
Fire stimulates grown and maintains some ecological systems.
8. C
In a fire, potassium and phosphorus remain in the ash.
9. C
A fire requires a combustible> material, and an oxidizer and a heat source.
10. B
A catalyst is a substance that is not consumed, when added, in any chemical reaction during combustion, but which enables the reactants to combust more readily.
11. C
Fire can be intensified by increasing the fuel and/or the oxidizer. Choice A is plausible, but choice C is the best choice.
12. B
Applying water to a fire removes heat faster than the fire can produce it
13. B A fire can be intensified by increasing the ambient temperature so the fire’s own heat is better able to sustain combustion.
14. B
Both gravity and convection are necessary to provide a continuous fuel supply and remove un-combusted particles and gases.
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Modified: August 10th, 2018 August 10th, 2018
Published: May 11th, 2015
Thanks but it so tricky
Thanks
Thanks
This was great. I wish that I could find more of these.
thanks!