问题
选择题
In the cross-lake swimming race, a boat will be ____in case of an emergency.
A．standing by
B．turning on
C．getting on
D．running on
答案
A
句意：有船只严阵以待，预防紧急情况。stand by 为不及物短语：to wait and be ready for action if needed 准备行动；待机；turn on 打开；get on进展；run down撞倒。根据句意，B 、C、D 三项均不符合。