长方形中相邻两边是互相垂直的．______．
由根据长方形的特征可知：长方形相邻的两条边互相垂直，原题说法正确，
故答案为：√．
19. I wondered_____that made him so upset.
A． how it was
B． which did it
C． what it was
D． who did it
