例一：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.
例二：Another major discovery was made in Egypt in 1989. Several skeletons of another early whale, Basilosaurus, were found in sediments left by the Tethys Sea and now exposed in the Sahara desert. This whale lived around 40 million years ago, 12 million years after Pakicetus. Many incomplete skeletons were found but they included, for the first time in an archaeocyte, a complete hind leg that features a foot with three tiny toes. Such legs would have been far too small to have supported the 50-foot-long Basilosaurus on land. Basilosaurus was undoubtedly a fully marine whale with possibly nonfunctional, or vestigial, hind legs.
It can be inferred that Basilosaurus bred and gave birth in which of the following locations ○On land
○Both on land and at sea
○In shallow water
○In a marine environment
例三：Nearly any kind of plant of the forest understory can be part of a deer's diet. Where the forest inhibits the growth of grass and other meadow plants, the black-tailed deer browses on huckleberry, salad, dogwood, and almost any other shrub or herb. But this is fair-weather feeding. What keeps the black-tailed deer alive in the harsher seasons of plant decay and dormancy? One compensation for not hibernating is the built-in urge to migrate. Deer may move from high-elevation browse areas in summer down to the lowland areas in late fall. Even with snow on the ground, the high bushy understory isexposed; also snow and wind bring down leafy branches of cedar, hemlock, red alder, and other arboreal fodder.
It can be inferred from the discussion in paragraph 2 that winter conditions
○ Cause some deer to hibernate
○ Make food unavailable in the highlands for deer
○ Make it easier for deer to locate understory plants
○Prevent deer from migrating during the winter
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