Search crews in the southern Indian Ocean are urgently trying to relocate electronic transmissions they believe came from the missing Malaysian airliner's black box. No signal has been heard since Sunday when U.S. Navy equipment detected two distinct sounds consistent with acoustic pings from the plane's flight data and cockpit voice recorders. _________________________ 搜救人员在南印度洋正迫切地对他们认为是疑似失联马航黑匣子的信号进行重新定位.周日,美国海军设备曾探测到两组清晰信号,与失联客机飞行数据和驾驶舱的声音记录器发出的声波脉冲一致.但自那以后就再也没探测到任何信号. _________________________
