GRE Text Completion: JiJing 1373-GRE填空机经1373题 - 8241KPP82Q21O3C5A

The (i)____________ current-generation solar cells are (ii)____________: although experimental cells have reached efficiencies greater than 40 percent, most commercially available cells in the early part of the twenty-first century still struggle to get past about 20 percent. A. attractions of B. clear C. limitations of D. unmatched E. improvements in F. misunderstood