alternates
名词 alternate:
someone who takes the place of another person
同义词:surrogate, alternate, replacement
动词 alternate:
go back and forth; swing back and forth between two states or conditions
exchange people temporarily to fulfill certain jobs and functions
同义词:alternate
be an understudy or alternate for a role
同义词:understudy, alternate
reverse (a direction, attitude, or course of action)
同义词:interchange, tack, switch, alternate, flip, flip-flop
do something in turns
同义词:alternate, take turns