1, vertical
Judging that a straight line is perpendicular to the plane: If a straight line is perpendicular to two intersecting (non-parallel) straight lines in the plane, then the straight line is perpendicular to the plane.
The property that a straight line is perpendicular to a plane: If a straight line is perpendicular to a plane, then it is perpendicular to all the straight lines in this plane.
Step 2 be parallel
Judging that the straight line is parallel to the plane: if the straight line is parallel to a straight line in the plane but not in the plane, it is parallel to the plane.
The property that a straight line is parallel to a plane: If a straight line is parallel to a plane, then the straight line is parallel to "the plane passes through the intersection of this straight line and this plane".
3. Belong to
Judge that a straight line belongs to a plane: if two points on a straight line are in this plane, then the straight line is in this plane.
The property that a straight line belongs to a plane: if it always belongs to a plane, then everything on this straight line is in this plane.
These are the most important, basic and commonly used judgment methods and properties. If you use it flexibly, such problems will be solved (easier said than done, I suggest doing more exercises). Especially the vertical relationship, which has the most applications and the most complicated changes, should be highly valued.