Two thirds of the forest ____ pine trees,which ___ at least three for four meters in height.a.are; are b.is; is c.is; are选A,2/3的树林是松树怎么第一空用复数呢?

Two thirds of the forest ____ pine trees,which ___ at least three for four meters in height.a.are; are b.is; is c.is; are选A,2/3的树林是松树怎么第一空用复数呢?
Two thirds of the forest ____ pine trees,which ___ at least three for four meters in height.
a.are; are b.is; is c.is; are
选A,2/3的树林是松树怎么第一空用复数呢?

Two thirds of the forest ____ pine trees,which ___ at least three for four meters in height.a.are; are b.is; is c.is; are选A,2/3的树林是松树怎么第一空用复数呢?
这里并不是因为thirds,而是因为forest和people一样是一个集合名词.一般表示复数.One third of the forest后也要用are

Two thirds of the forest 因为third加s了
如果是one third 就要用单数