In how many points can two distinct lines at the most intersect?

Define the following terms :

(i) Line segment

(ii) Collinear points

(ii) Parallel lines

(iv) Intersecting lines

(v) Concurrent lines

(vi) Ray

(vii) Half-line

How many lines can pass through a given point?

Given two points P and Q, find how many line segments do they determine.

Name the line segments determined by the three collinear points P, Q and R.