I think of the materials I listened to at the beginning of the exam easy. A. two thirds;

I think of the materials I listened to at the beginning of the exam easy.
A. two thirds; is
B. second three; are
C. two thirds; are
D. two third; are

A. two thirds; isB. second three; are(答案→)C. two thirds; areD. two third; are解析：句意：我认为这个学期初我听过的三分之二的材料是简单的。two thirds三分之二，表示分数时分子用基数词，分母用序数词，分子超过1时，分母的序数词要加s；material是可数名词，所以谓语动词要用复数，故选C。

我明天再问问老师，叫他解释下这个问题