The first technique is match on action you can see this as the actor opens the door and walks through, it then cuts and you see him walking through into the room and shutting the door. This is a good techniques as it helps the film to flow better and keep its consistency throughout.
The next technique is shot reverse shot, this is generally used when a conversation is happening, it shows the reactions and emotions of characters well and allows a conversation in a film to flow better. It also allows the audience to feel they are more involved with the film.
A technique used throughout the task is the 180 degree rule. This means that cameras should stay on one side of a line, the line is perpendicular o the cameras viewpoint in the establishing shot of the scene. Breaking this rule would cause confusion in the audience.