托福TPO25阅读长难句

托福TPO5阅读长难句

　　TPO25: The Surface of Mars

　　1. It is no accident that Maxwell Mons on Venus and the Hawaiian shield volcanoes on　Earth rise to about the same height (about 10 kilometers) above their respective　bases-Earth and Venus have similar surface gravity.

　　2. Scientists have no direct evidence for recent or ongoing eruptions, but if these volcanoes　　were active as recently as 100 million years ago (an estimate of the time of last eruption　based on the extent of impact cratering on their slopes), some of them may still be at leastintermittently active.

　　TPO25: The Decline of Venetian Shipping

　　1. In the fifteenth century there was little problem recruiting sailors to row the galleys　(large ships propelled by oars): guilds (business associations) were required to provide　rowers, and through a draft system free citizens served compulsorily when called for.

　　2. The step from buying foreign timber to buying foreign ships was regarded as a short one,　especially when complaints were heard in the latter sixteenth century that the standards　and traditions of the Arsenale were running down.

　　3. Historian Frederic Lane observes that after the loss of ships in battle in the late　sixteenth century, the shipbuilding industry no long had the capacity to recover that it had　displayed at the start of the century.

　　4. The conventional explanation for the loss of Venetian dominance in trade is　establishment of the Portuguese direct sea route to the East, replacing the overland Silk　Road from the Black sea and the highly profitable Indian Ocean-caravan-eastern　Mediterranean route to Venice.

　　5. Prices of spices delivered by ship from the eastern Mediterranean came to equal those of　spices transported by Paortuguese vessels, but the increase in quantity with both routes in　operation drove the price far down.

　　6. In the fifteenth century there was little problem recruiting sailors to row the galleys　(large ships propelled by oars): guilds (business associations) were required to providerowers, and through a draft system free citizens served compulsorily when called for.

　　托福TPO5阅读长难句TPO25: The Evolutionary Origin of Plants

　　1. Water temperature can fluctuate seasonally or even daily and changing level of rainfall　　can lead to fluctuations in the concentration of chemical in the water or even to period in　which the aquatic habitat dries up.

　　2. From a plant’s evolutionary view point, however, it was also a land of opportunity, free　of competitors and predators and full of carbon dioxide and sunlight (the raw materials for　photosynthesis, which are present in far higher concentrations in air than in water).

　　3. They include roots or root like structures, a waxy cuticle that covers the surfaces of　leaves and stems and limits the evaporation of water, and pores called stomata in leaves　and stems that allow gas exchange but close when water is scarce, thus reducing water　loss.

　　4. These include conducting vessels that transport water and minerals upward from the　roots and that move the photosynthetic products from the leaves to the rest of the plant　body and the stiffening substance lignin, which support the plant body, helping it expose　maximum surface area to sunlight.

　　5. So the most successful groups of land plants are those that evolved methods of fertilized　　sex cell dispersal that are independent of water and structures that protest developing　embryos from drying out.