stand-by

名词 stand-by:

1. something that can be relied on when needed
   同义词：standby
2. an actor able to replace a regular performer when required
   同义词：understudy, standby

动词 stand-by:

1. not act or do anything
   同义词：stand by
2. be available or ready for a certain function or service
   同义词：stand by, stick around, stick about
3. be loyal to
   同义词：stand by, stick by, stick, adhere

形容词 stand-by:

1. ready for emergency use
   同义词：standby

1. A special team of police were kept on standby during the time of violence.
   在发生暴乱期间，经常有一支警察特别小分队处于整装待命状态。