单词	主迹
释义	主迹principal trace
随便看	time distance time distance curve time-distance curve time-distance graph time distance relay time distance scale time distribution time diversity time diversity duplexing time divided network time division time-division time division channel time-division command time division common control time division control access time division data link time-division demultiplexing time-division digital switching time division duplex time division duplex code division multiple access time division duplexing time division exchange time division exchange--tdx time division exchange，tdx