understudy

名词 understudy:

1. an actor able to replace a regular performer when required
   同义词：standby

动词 understudy:

1. be an understudy or alternate for a role
   同义词：alternate

1. The leading man got laryngitis but his understudy stepped into the breach and gave an excellent performance.
   演主角的男演员得了喉炎，不过他的替角代替了他，而且表演得极为出色。
2. An understudy who filled in at the last minute.
   在最后一分钟才临时替补的演员
3. The understudy was substituted when the leading actor fell ill.
   主角演员患病，由替角代替演出。