In this wiring, the source is at the switch and 3-wire cable runs from there to the fan/light. The switch controls the light and the source is spliced through to the fan. With this arrangement, the fan is controlled by a pull-chain on the motor housing and the light is controlled with the switch. The neutral and ground wires are also spliced through to the fan/light.
Here GFCI’s are wired to a double-pole circuit breaker with the source split to provide 120 volts to two sets of receptacles. The neutral from the source is shared by both sets. Single-location protection is provided by each receptacle.
Here one ground fault circuit interrupter protects multiple duplex receptacles coming after it, known as multiple-location protection. Two-wire cable runs from the gfci to all the following receptacles. The line terminals on the gfci are connected to the circuit source and the load terminals are connected with a pigtail splice to each of the following receptacles. This keeps each duplex connected directly to the gfci.
This gfci wiring provides protection to a duplex receptacle. By connecting the load terminals on the last gfci, the receptacle is protected and can be used just as if it were one of the gfci receptacles. One ground fault circuit interrupter at the beginning of the circuit can be used in the same way to protect multiple, subsequent receptacles as illustrated in the diagram below.