(of two kinds of things) first one and then the other

substitute

a person given a responsibility (especially a representative sent to a meeting)

representative, often governmental

a person who is (to be) given another person's authority etc

assistant, agent

(an instance, act, of) exchanging things

trade; deal

an act of recovering

the act of returning to normal

(an instance of) the act of removing

the state of being removed

to restore (something worn or damaged) to good condition; to put (a bad or wrong act or result) right again

restoration, fixing

concerned with going or coming back; (an instance of) coming, going, giving, sending, putting, back; an official report or statement

coming again

submarine; substitute; subscription; subtitles

substitute

a person or thing taking the place of, acting for, another

alternative

a person or thing that succeeds another

heir

acting as a substitute

person or thing that acts as

a person learning to, able to, take the place of another (especially an actor)

substitute