问题
选择题
. Emergency line operators must always ________calm and make sure that they get all the information they need to send help.
A．grow
B．appear
C．become
D．stay
答案
答案：D
词义辨析。A. 生长 B. 出现 C. 变成 D. 坚持；停留。句意：紧急线路操作员必须一直保持冷静并确信他们得到了所有需要发送的帮助信息。故选D。