横向
1
Repeated addition
3
Collection of distinct elements
5
U-shaped curve of a quadratic function
纵向
2
Steepness of a line
4
Number greater than zero
5
Lines that never intersect
6
Number divisible only by 1 and itself
7
Round shape with all points equidistant
8
Part of a whole number
9
Part of a circle's circumference