¡¡¡¡1. In terms of physics£¬ the characteristic feature of the roller coaster is the car's potential energy£¬ gained through their being lifted by a chain drive through the Earth's gravity to the top of the first drop£¬ have been converted to kinetic energy by the time the ride ends.
¡¡¡¡2. During the early years of European settlement on a continent that was viewed to be ¡°wilderness¡± by the newcomers£¬ Native Americans£¬ intimately knowing the ecology of the land£¬ were a help in the rescuing of many Pilgrims and pioneers from hardship£¬ or even death.
¡¡¡¡3. Even the state have spent ten years and seven million dollars plan a reservoir along the Ubi River£¬ the project will have to be abandoned because of the river becoming so heavily polluted.
¡¡¡¡4. Machines replacing human labor£¬ there are wide anticipation that the workweek would continue to become shorter.
¡¡¡¡£¨A£© Machines replace human labor£¬ there are wide anticipation that
¡¡¡¡£¨B£© When machines replaced human labor£¬ there are wide anticipation
¡¡¡¡£¨C£© As machines replaced human labor£¬ it was widely anticipated that
¡¡¡¡£¨D£© In so far as machines replaced human labor£¬ it was widely anticipated
¡¡¡¡£¨E£© Human labor being replaced by machines£¬ there was wide anticipation that
¡¡¡¡5. Socrates could have fled from Athens after he was sentenced to death£¬ but he refused to do it.
¡¡¡¡£¨A£© Socrates could have fled from Athens after he was sentenced to death£¬ but he refused to do it.
¡¡¡¡£¨B£© After he was sentenced to death£¬ Socrates might have fled from Athens£¬ but he refused to do it.
¡¡¡¡£¨C£© After he was sentenced to death£¬ Socrates could have fled from Athens£¬ but he refused to do so.
¡¡¡¡£¨D£© Refusing to fled from Athens£¬ Socrates could have done so after he was sentenced to death.
¡¡¡¡£¨E£© Socrates could have fled from Athens but refused to after he was sentenced to death.
¡¡¡¡6. It is possible that Native Americans originally have migrated to the Western Hemisphere over a bridge of land that once existed between Siberia and Alaska.
¡¡¡¡£¨A£© have migrated to the Western Hemisphere over a bridge of land that once existed
¡¡¡¡£¨B£© were migrating to the Western Hemisphere over a bridge of land that existed once
¡¡¡¡£¨C£© migrated over a bridge of land to the Western Hemisphere that once existed
¡¡¡¡£¨D£© migrated to the Western Hemisphere over a bridge of land that once existed
¡¡¡¡£¨E£© were migrating to the Western Hemisphere over a bridge of land existing once
¡¡¡¡7. As envisioned by researchers£¬ commercial farming of lobsters will enable fisheries to sell the shellfish year-round£¬ taking advantage of off-season demand£¬ standardize its sizes and colors£¬ and to predict sales volume in advance.
¡¡¡¡£¨A£© taking advantage of off-season demand£¬ standardize
¡¡¡¡£¨B£© taking advantage of off-season demand£¬ to standardize
¡¡¡¡£¨C£© taking advantage of off-season demand£¬ standardizing
¡¡¡¡£¨D£© take advantage of off-season demand£¬ standardizing
¡¡¡¡£¨E£© take advantage of off-season demand£¬ to standardize
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