generally PMOSFET bulk(substrate) terminal is connected to more positive voltage in the circuit
but
can we connect PMOSFET bulk(substrate) terminal to ground
what happens if bulk terminal is connected to ground
It will be badly polarised. There is a PN junction between p-substrate and n-well. Also PN junctions beween n-well and p-MOSFET drain/source. These junctions have to be in reverse bias.
In some design it may connect with source to avoid body effect, otherwise its better to connect with higher potential to avoid pn junction with forwardbias bettween source and bulk