(1/3)下面这道题应选择哪个答案、为什么?(_)of this area (_)covered with green trees and gr

题目

(1/3)下面这道题应选择哪个答案、为什么?(_)of this area (_)covered with green trees and gr

答案

One third of this area is covered with forest.题不完整,理同此句.第一空填（百）分数,或three- fourths,或75 percent,主语是this area,后一空定为is.