问题
选择题
A curve is a line ______ no part is straight and which has no angle.
A．that
B．whose
C．in which
D．of which
答案
答案：D
题目分析：句意：曲线是一条线它没有部分是直的而且没有角。这里是定语从句先行词是a curve，定语从句中是no part of the curve is straight，所以缺少介词of+关系代词（which），所以选D.