单项选择题
A、 Jerry stayed in a room on the third floor for an hour. B、Jerry was absent when the discussion was being held. C、Nobody but the woman noticed that Jerry was absent. D、Jerry did not leave room 405 until an hour had passed.
A、 He has managed to sell a number of cars. B、 He is contented with his current position. C、 He might get fired. D、 He has lost his job
A. Researchers will test in more seismically active places. B. Researchers will drill more deep holes along the fault lines. C. Researchers need to eliminate some factors which might affect seismic readings. D. Researchers need to do more in their detecting systems.