By the eighteenth century, Britain was experiencing a severe shortage of energy. Because of the growth of population, most of the great forests of medieval Britain had long ago been replaced by fields of grain and hay. Wood was in ever-shorter supply, yet it remained tremendously important. It served as the primary source of heat for all homes and industries and as a basic raw material. Processed wood (charcoal) was the fuel that was mixed with iron ore in the blast furnace to produce pig iron (raw iron). The iron industry’s appetite for wood was enormous, and by 1740 the British iron industry was stagnating. Vast forests enabled Russia to become the world’s leading producer of iron, much of which was exported to Britain. But Russia’s potential for growth was limited too, and in a few decades Russia would reach the barrier of inadequate energy that was already holding England back.

What can be inferred from paragraph 1 about Britain’s short supply of wood in the eighteenth century?

A) Wood from Britain’s great forests was being exported to other countries for profit.

B) A growing population had required cutting down forests to increase available land for farming.

C) Larger families required the construction of larger homes made from wood.  

D) What was left of the great forests after the medieval period was being strictly protected.

接下来聊聊，推断题第2个策略：对比。对比有两点。同一事物，不同时间。即时间点，事件点前后取反。

举个例子先：9点开始上课。能推出什么？

答案：9点之前不上课。这就是时间点前后取反。

再举个例子：工业革命之前，英国城市很少。能推出什么？

答案：工业革命之后，英国城市很多。事件点前后取反。

This was before the steam locomotive, and canal building was at its height. The companies building the canals to transport coal needed surveyors to help them find the coal deposits worth mining as well as to determine the best courses for the canals. This job gave Smith an opportunity to study the fresh rock outcrops created by the newly dug canal. He later worked on similar jobs across the length and breadth of England, all the while studying the newly revealed strata and collecting all the fossils he could find. Smith used mail coaches to travel as much as 10,000 miles per year. In 1815 he published the first modern geological map, “A Map of the Strata of England and Wales with a Part of Scotland,” a map so meticulously researched that it can still be used today.

 Which of the following can be inferred from paragraph 2 about canal building?

○ Canals were built primarily in the south of England rather than in other regions.

○ Canal building decreased after the steam locomotive was invented.

○ Canal building made it difficult to study rock strata which often became damaged in the process.

○ Canal builders hired surveyors like Smith to examine exposed rock strata.

Oil pools are valuable underground accumulations of oil, and oil fields are regions underlain by one or more oil pools. When an oil pool or field has been discovered, wells are drilled into the ground. Permanent towers, called derricks, used to be built to handle the long sections of drilling pipe. Now portable drilling machines are set up and are then dismantled and removed. When the well reaches a pool, oil usually rises up the well because of its density difference with water beneath it or because of the pressure of expanding gas trapped above it. Although this rise of oil is almost always carefully controlled today, spouts of oil, or gushers, were common in the past. Gas pressure gradually dies out, and oil is pumped from the well. Water or steam may be pumped down adjacent wells to help push the oil out. At a refinery, the crude oil from underground is separated into natural gas, gasoline, kerosene, and various oils. Petrochemicals such as dyes, fertilizer, and plastic are also manufactured from the petroleum.

Which of the following can be inferred from paragraph 3 about gushers? 

○They make bringing the oil to the surface easier.

○They signal the presence of huge oil reserves.

○They waste more oil than they collect.

○They are unlikely to occur nowadays.

Paragraph 1: It should be obvious that cetaceans—whales, porpoises, and dolphins—are mammals. They breathe through lungs, not through gills, and give birth to live young. Their streamlined bodies, the absence of hind legs, and the presence of a fluke1 and blowhole2 cannot disguise their affinities with land dwelling mammals. However, unlike the cases of sea otters and pinnipeds (seals, sea lions, and walruses, whose limbs are functional both on land and at sea), it is not easy to envision what the first whales looked like. Extinct but already fully marine cetaceans are known from the fossil record. How was the gap between a walking mammal and a swimming whale bridged? Missing until recently were fossils clearly intermediate, or transitional, between land mammals and cetaceans.

Which of the following can be inferred from paragraph 1 about early sea otters? 

○It is not difficult to imagine what they looked like.

○There were great numbers of them.

○They lived in the sea only.

○They did not leave many fossil remains.