Central office telephone equipment serving subscribers at one location on a private automatic branch exchange basis. The system allows such servicesas direct inward dialing,direct distance dialing,and console switchboards.是什么意思_Central office telephone equipment serving subscribers at one location on a private automatic branch exchange basis. The system allows such servicesas direct inward dialing,direct distance dialing,and console switchboards.在線(xiàn)翻譯_英語(yǔ)_讀音_用法_例句