In the present invention, regarding a narrowband used in a subframe for transmitting uplink data, if a switch is made from a first narrowband used in a first subframe to a second narrowband that is different from the first narrowband, with respect to a second subframe continuing to the first subframe, a final one symbol of the first subframe and an initial one symbol of the second subframe are punctured and set as a retuning time to transmit the uplink data in the first narrowband and the second narrowband.