The question will ask youto explain the main concept or issue using the points and examplesthat were given in the lecture. So basically it's a very straight forward summary.
這是ETS官方視頻中對Task 4所提出的要求，注意劃線部分內容：你必須解釋清楚main concept或者issue。這就是高分關鍵!!!
很多同學在回答第四題的時候，只是在單純地summarize the lecture(總結講座)，而忽略了題目中隱藏的“暗線”，也就是高分要求中的points和examples。
Fair級別的答案：For instance, a species of bird takes in soil sometimes. Because it's toothless, eating soil can help it with its digestion. 在這個答案中并沒有體現出soil起到的具體作用，因此只能得fair。
再看Good級別的答題：Wild pheasant is a good example. It is toothless, so it has to take in soil sometimes to help it grind up giant seeds with hard shells into smaller pieces, to make it easier to digest. 這個答案中包含了3點重要信息，toothless, giant seeds with hard shells and grind up into smaller pieces，從而充分論證了soil在消化過程中起到的具體作用。
Today, we're going to discuss forest fires. Generally, when a forest fire occurs, the animals in the area will of course scurry away from the fire. Some animals, though, actually benefit from forest fires and so will follow them because forest fires can help them meet their survival needs. Let's discuss two benefits forest fires could have for these animals.
One benefit is that they can make it easier for predators to find food.A forest fire will force animals out of their hiding places, which predators make use of because fleeing animals are much easier to catch than they normally are when they are hiding deeply.
For example, scientists have observed skunks doing this. These animals will go to the edge of a forest fire and wait there in order to catch all the insects running out of the burning forest, which is a much easier way to catch insects than the normal way of pecking for them on the ground.
Another benefit forest fires could have is to help provide a good place for the development of young animals.Forest fires can make an otherwise harmful environment more suitable for their development.
For example, Burch trees in the forest are poisonous to ants. They have a special chemical that keeps ants away. But after a fire, ants will seek out these trees because the trees are dead and ants are able to lay their eggs in the trees without being hurt by the chemical. The young ants use the trees' nourishment until they mature into adult ants.
再次強調，闡述example的時候，一定要想著to example the main concept or the issue。