5us，协同业务的同步精度为3us（15kz）、0.7us（30khz）、0.19us（120khz）（）

合并单元在外部同步时钟信号消失后，至少能在内继续满足4us的同步精度要求 She told us that her brother ______ the Army for 3 years. SDH帧结构以us为帧同步周期（） Not only ____ strict with us, but also ____ for us. TD-LTE系统对时钟的要求很高，要求精度小区3us，为了保证空口时钟同步，设计使用GPS作为每个基站的基准时钟，GPS时钟精度为 us [5sE:kEs] We hope you could _____ us a special discount of 3 on orders. India exports US$150 billion IT products to the US（） We ________ a parent to care for us, to forgive us our errors, and to save us from our childish mistakes. 调试超声波检测仪时,测得t0=5us,已知某测点声距L=40cm,仪器显示声时为105us,则超声波在混凝土中传播的声速为（） will it take us to fly to Hainan and will the trip to Hainan cost us? Though the teacher is strict _____ us, she is good to us. [ ] Not only ______ prepare lunch for us, but also _______ clothes for us. Their sudden attack made us more () of the danger around us Not only（ ）us light, but it also gives us heat. We（）your letter of Nov.3 asking us to make a quotation. Professor Wu told us that by the end of the year he _______ here for 3 years. 3.4NEWS2 1: Russia and Germany.|The US and Germany.|The US and Russia.|The US and the UK. ______ frightened us ______ a tiger turned up suddenly in front of us. Though to see us, the professor gave us a warm welcome.