rear guard

柯林斯词典

1. N-SING In a battle, the rearguard is a group of soldiers who protect the back part of an army, especially when the army is leaving the battle. (尤指战场上军队撤退时的)后卫部队['the' N]
2. PHRASE If someone is fighting a rearguard action or mounting a rearguard action, they are trying very hard to prevent something from happening, even though it is probably too late for them to succeed. 负隅顽抗; 最后一搏[journalism]
Mr. Lin looks increasingly like someone fighting a rearguard action to keep their job. 林先生越来越像是为了保住自己的工作而作最后一搏的那些人。