This clip is excerpted from the movie “Witness for the Prosecution”. This movie is mainly shot from the third-person perspective, and it mainly tells the story of a lawyer defending the male protagonist accused of murder.This fragment tells the conversation that occurred when the protagonist’s wife told the lawyer that she would appear as a witness in court.  The types of shots used in this clip are motion shots (medium shots) and fixed shots (medium shots).  The beginning part of the clip is to switch back and forth with a fixed lens.In the dozens of seconds which Mrs. Wall opened the curtains to continue the conversation with the lawyer and walked forward, here is to track a series of actions of Mrs. Wall through a long lens to show her calm and unique temperament.  The shooting of this kind of motion shots makes the picture more natural and can better substitute the audience into the movie plot.The last part changes from motion shot to fixed shot(medium shot).  Generally, the fixed shot is conducive to the performance of a static environment and can bring a different feeling to the audience.This part is to show the actor’s detailed movements and eyes.  For example, the lawyer said to Mrs. Wall, “Do you know that the British law does not allow the wife to say anything unfavorable to her husband in court?” Mrs. Wall said that the man is not her husband, but at this time her eyes  Started to move left and right non-stop.  This means that she is starting to think of a solution.This detail is to achieve contrast for the later plot.  The lens type of the entire movie is that the number of fixed top lenses is much larger than that of motion shots, and some long shots with comprehensive sports account for a large proportion of these motion shots. For this part, a few motion shots used to show it.