位于中国新疆的塔里木盆地北缘的（），是中国最大的内流河。
参考答案：塔里木河
-Yuan Longping, one of the greatest scientists in China, __________ as "father of hybrid rice".
-We are proud of him.[ ]
A. is regarded
B. has regarded
C. is regarding
D. regards
一个整式与x2﹣y2的和是x2+y2，则这个整式是 [ ]
A．2x2
B．2y2
C．﹣2x2
D．﹣2y2
