substituting
  代入
  Sub·stit·ute v. t. [imp. & p. p. Substituted p. pr. & vb. n. Substituting ]  To put in the place of another person or thing; to exchange.
     Some few verses are inserted or substituted in the room of others.   --Congreve.
  ◄ ►
  substituting
       n : working as a substitute for someone who is ill or on leave
           of absence [syn: subbing]