What should p waves look like in lead v1? what does it mean if different on some ekg?one will show completely positive,one fully negative,another biph

There can be a lot: of normal variability to the p-wave morphology in V1. More so in women. In general a biphasic or mostly upright p wave is usual. Certainly you could have an ectopic atrial activation in which case the morphology would be altered. Physical positioning (sitting, lying or at 30 degrees) for the EKG will also make a difference. Lead position too. Regardless it is usually of no clinical significance.