The main objective of mechanical practice is to help learners to absorb thoroughly the ________ of a language item.

A.meaning B.function C.context D.form

Passage 2 Among China's greatest art treasures are the Buddhist caves near Dunhuang. Their ancient frescoes and sculptures have survived wars, environmental damage, antiquities hunters, and the chaotic Cultural Revolution.Today domestic tourism is the biggest threat: the UNESCO World Heritage site has an optimal capacity of 3,000 per day, but peak times can see twice that many visitors.The Mogao Grottoes are especially vulnerable to mass tourism. Their ecosystems are fragile. A buildup of humidity and carbon dioxide from visitors' breath can lead to flaking and discoloration of wall paintings.To preserve the caves, the Dunhuang Academy is pioneering a project to digitize the site. Recently, the Arthur M. Sackler Gallery in Washington, D.C., offered a tantalizing glimpse at the undertaking. Donning 3-D glasses, visitors were transported into a breathtaking "virtual" Dunhuang grotto, known as Cave 220. The 3-D, interactive experience is flooded with vivid color, close-up details, moving images of flying bodhisattvas, even sound, "Dunhuang ranks as the single most important repository of early Chinese art. Here the great cultures of the World-Greek and Roman, Persian and Middle Eastern, Indian and Chinese-constantly interacted for over a millennium," said Mimi Gates, who formed the Dunhuang Foundation. “High resolution digitization will provide a lasting record ofthis artistic treasure for all mankind and can make it accessible beyond China."A dozen years ago, the Dunhuang Academy began cooperating with foregoing institutions to conserve the treasures. Among the projects, one used a camera to create a digital archive of the caves. The results will be used in the academy which planned $40 million state-of-the-art visitor center which will present virtual tour of the caves to save the real site wear and tear. The scope of the project isdaunting. It requires 20 minutes or so to record a 9-square-meter fresco, and there are 492 caves with murals inside. But the Sackler exhibit proved how enthralling the single virtual cave can be.Real caves provide no lightbulbs. Once they reach critical levels of moisture and temperature, they are shut to the public. Only a few dozen caves are accessible at any given time. But the Sackler’s virtual tour was different. One of the most popular features was the "magnifying glass", which can zoom in on, say, a zither depicted in a mural. The instrument appears to pop out of the wall, enlarge, and then rotate in space. Visitors can also "flip" back and forth between the intricate Tang-dynasty mural and a later, cruder Sung-dynasty fresco.To help Cave 220's Tang dancer paintings magically come to life, two Chinese performers were flown to the Applied Laboratory for Interactive Visualization and Embodiment (ALIVE) in a Hong Kong university. For three days the dancers were filmed performing intricate steps, fluid movements, and careful manipulation of long, sinuous ribbons. They appeared in the Sackler tour, dancing as if in midair, clad in brightly colored Tang costume. ALIVE's project manager said while he's become intimately familiar with the images Cave 220, he hasn't been there yet. 661 can't wait to visit the real thing."

_________ enough time and money, the investigators would have been able to discover more evidence in this case.

A.Giving B.Given C.To give D.Being given

一般来说，认识和研究土壤需要分析土壤剖面。在土壤剖面中，包含有机质积质淋溶层的是（）。
A.表土层B.心土层C.母质层D.母岩层

人体血管在动脉与动脉、静脉和静脉、动脉和静脉之间的直接连通皆称为（）。
A.血管吻合B.微循环C.肺循环D.体循环

In Rome, tourists may easily get _________ because all the streets look the same.

A.disoriented B.deluded C.distracted D.delineated