A terminal device, wherein the terminal device is a first terminal device comprising: a transceiving unit, configured to receive sidelink control information, SCI, transmitted by a second terminal device, wherein the SCI indicates a time-frequency resource used by the second terminal device to transmit a data channel;a determining unit, configured to determine that the SCI is in a first format or in a second format, wherein the SCI comprises a resource reservation bit, and the resource reservation bit in the SCI of the first format is not used to indicate whether the second terminal device reserves a time-frequency resource for next data transmission, and the resource reservation bit in the SCI of the second format is used to indicate whether the second terminal device reserves the time-frequency resource for the next data transmission; the transceiving unit is further configured to prohibit data transmission on a plurality of time-frequency resources distributed in accordance with a first time period if the determining unit determines that the SCI is in the first format, wherein the plurality of time-frequency resources correspond to the time-frequency resource indicated by the SCI; wherein the first terminal device further comprises a measurement unit, and the measurement unit is configured to: measure reference signal received power, RSRP, of the data channel transmitted by the second terminal device; wherein the transceiving unit is configured to: prohibit data transmission on the plurality of the time-frequency resources distributed in accordance with the first time period, if the RSRP measured by the measurement unit is greater than or equal to a preset threshold. a transceiving unit, configured to receive sidelink control information, SCI, transmitted by a second terminal device, wherein the SCI indicates a time-frequency resource used by the second terminal device to transmit a data channel;a determining unit, configured to determine that the SCI is in a first format or in a second format, wherein the SCI comprises a resource reservation bit, and the resource reservation bit in the SCI of the first format is not used to indicate whether the second terminal device reserves a time-frequency resource for next data transmission, and the resource reservation bit in the SCI of the second format is used to indicate whether the second terminal device reserves the time-frequency resource for the next data transmission; the transceiving unit is further configured to prohibit data transmission on a plurality of time-frequency resources distributed in accordance with a first time period if the determining unit determines that the SCI is in the first format, wherein the plurality of time-frequency resources correspond to the time-frequency resource indicated by the SCI; wherein the first terminal device further comprises a measurement unit, and the measurement unit is configured to: measure reference signal received power, RSRP, of the data channel transmitted by the second terminal device; wherein the transceiving unit is configured to: prohibit data transmission on the plurality of the time-frequency resources distributed in accordance with the first time period, if the RSRP measured by the measurement unit is greater than or equal to a preset threshold. measure reference signal received power, RSRP, of the data channel transmitted by the second terminal device; wherein the transceiving unit is configured to: prohibit data transmission on the plurality of the time-frequency resources distributed in accordance with the first time period, if the RSRP measured by the measurement unit is greater than or equal to a preset threshold.