4. Which of the following would be the most likely topic for a paragraph that logically continues the passage?主题题（写法性）
(A) The kinds of plants normally found in arid regions
(B) The effect of variation in lake levels on pollen distribution
(C) The material best suited to preserving signals of climatic changes
(D) Other criteria invoked by paleoclimatologists when choosing a method to determine past climatic conditions（E）
(E) A third method for investigating past climatic conditions本文缺正确的解决方案
5. The author discusses lake levels in the southwestern United States*5 in order to举例作用题（窍门法：illustrate, give/provide an example of；标准法：For instance, For example, such as, like——结论在前）
(A) illustrate the mechanics of the relationship between lake level, evaporation, and precipitation
(B) provide an example of the uncertainty*5B involved in interpreting lake levels
(C) prove that there are not enough ancient lakes with which to make accurate correlations
(D) explain the effects of increased rates of evaporation on levels of precipitation（B）
(E) suggest that snow-line elevations are invariably more accurate than lake levels in determining rates of precipitation at various points in the past
6. It can be inferred from the passage that an environmental signal*6（第二、第三个标准都讲到了，不过这里考的是第三个标准） found in geological material would not be useful to paleoclimatologists if it改善题的变体（回文中找优点——本文是要求、标准，然后取非）
(A) had to be interpreted by modern chemical means
(B) reflected a change in climate rather than a long-term climatic condition
(C) was incorporated into a material as the material was forming
(D) also reflected subsequent environmental changes*6D（D）
(E) was contained in a continental rather than a marine sequence
7. According to the passage, the material used to determine past climatic conditions must be widespread*7 for which of the following reasons?直接事实题（不要用非出题段落内容来解题）
I. Paleoclimatologists need to make comparisons between periods*7 of geological history.
II. Paleoclimatologists need to compare materials that have supported a wide variety of vegetation.
III. Paleoclimatologists need to make comparisons with data collected in other regions*7.
(A) I only
(B) II only
(C) I and II only
(D) I and III only（D）
(E) II and III only
8. Which of the following can be inferred from the passage about the study of past climates in arid and semiarid regions（第二段和第三段，定位太广，只能挨个答案看）?信息题BDE无，C反
(A) It is sometimes more difficult*8A to determine past climatic conditions in arid and semiarid regions than in temperate regions.
(B) Although in the past more research没讲过 has been done on temperate regions, paleoclimatologists have recently turned their attention to arid and semiarid regions.
(C) Although more information说反了 about past climates can be gathered in arid and semiarid than in temperate regions, dating this information is more difficult.
(D) It is difficult to study the climatic history of arid and semiarid regions because their climates have tended to vary more原因错了 than those of temperate regions.（A）
(E) The study of past climates in arid and semiarid regions has been neglected不对 because temperate regions support a greater variety of plant and animal life.
责任编辑：sealion1986
