A．对 B．错紧急呼叫(SOS)需要进行附着以后才能发起的网络服务（ ）……

未分类题Which of the following can best sum up the author's overall reaction to her adult son's positive response to spring cleaning?A.Surprised and skeptical.B.Elated and hesitant.C.Relieved and optimistiC.D.Optimistic and hesitant.

单项选择题一组数据的分布曲线呈双峰状态，据此可以推测该组数据中可能有两个（2012年全国统考） A、中数 B、众数 C、平均数 D、几何平均数

单项选择题以下哪些不是交流传动技术的优点 A、功率因数高 B、电机体积、重量小 C、控制技术简单 D、电制动能量可以回馈电网

单项选择题不属于法洛四联症畸形组成的是 A、肺动脉狭窄 B、室间隔缺损 C、主动脉骑跨 D、右心室肥大 E、房间隔缺损

未分类题听力原文： The train I was traveling on was already half an hour latE.I had planned to arrive in Chicago at 7:00 in time to catch the 7:50 train to St. Louis, but there was no hope of that now. I explained the situation to the conductor who advised me to get off before Union Station and take a taxi. When the time came, he even helped me with my languagE.He wished mea good luck as I jumped off, and a few minutes later I was going towards the Union Station in a taxi. It was almost 7:50 when we stopped outside the station, I paid the driver quickly, carried my bags and hurried insidE.'The St. Louis train....'?' was all I had time to say to the first porter I saw. You can imagine my disappointment when he pointed to a train that was just moving out of the station.When did the train he was travelling on arrive in Chicago?A.At 7:00.B.At 7:50.C.In timE.D.Behind its timE.