OG 163[求助]

ytrrew

Found throughout Central and South America, the sloth hangs from trees by its long rubbery limbs, sleeping fifteen hours a day and moving so infrequently that two species of algae grow on its coat and between its toes. 请教sleeping....and moving...做什么成份？为什么可以这么用？ 谢谢

teyvhf

现在分词做状语。GMAT里很多这样的题。且举2例: As the price of gasoline rises, making alcohol distilled from cereal grain an attractive substitute, the price of bread and livestock feed are sure to increase. The root systems of most flowering perennials either become too crowded, resulting in losss of vigor, or spread too far outward, producing a bare center.