柯林斯詞典main line 1. N the trunk route between two points, usually fed by branch lines 乾線2. N (as modifier) 乾線的 a main-line station 3. V to inject a drug into a vein 將葯物注射進動脈[slang] 4. ADJ having an important position, esp having responsibility for the main areas of activity 有重要職位的 返回 main line劍橋詞典an important railway route between large towns or cities （鉄路的）乾線 the main line between New York and Philadelphia 連接紐約和費城的鉄路乾線 返回 main line