易错点一:下面三个图形哪些是圆柱体?答:A、B、C三个图形都是圆柱体。错解分析:对圆柱体的特征掌握得不准确。图B上、下两个面是大小不等的两个圆,不符合圆柱的特征,是圆台;图C上、下两个面是大小相等的圆,是斜圆柱,它不是由长方形旋转形成的,不是我们小学阶段所学的直圆柱(或正圆柱)。 Error-prone one: Which of the following three graphics which cylinder? A: A, B, C three graphics are cylindrical. Misunderstanding analysis: the characteristics of the cylinder mastered inaccurate. Figure B, the next two faces are two different sizes of the circle, does not meet the characteristics of the cylinder is a round table; Figure C, the next two faces are equal-sized circle is oblique cylinder, it is not formed by a rectangular rotation , Not the straight cylinder (or regular cylinder) we learned in the elementary school.