Your choice of lenses are important for the situation. A zoom lens is ideal for a wedding or event where you are constantly moving around. A prime lens is difficult to work with in these types of situations. Say you have a group shot at a wedding reception and need to get everyone in the photo. With a prime lens you need to backup but in many situation you will not have room to do so.You can have a wall, tables and other obstructions behind you. A 70 – 200mm zoom lens is ideal among wedding photographers however small zoom ranges are also recommended. You will mostly be shooting from 35mm up to the 85mm range.
50mm is closes to the human eye. 50mm is best for shooting portraits. 35mm can work but might stretch the appearance of your subject.