If the line AB is a non planar line, a [alpha, B [beta], and the plane alpha intersection beta equals C, then

If the line AB is a non planar line, a [alpha, B [beta], and the plane alpha intersection beta equals C, then

If AB is not coplanar, then AB is a straight line out of plane,
The positional relationship between C and a, B is that a, B has at most one straight line (a or b) parallel to C,
Otherwise, if a / / C, B / / C, then a / / B, then a, B are coplanar straight lines, not suitable
That is, C intersects a or B or a B,