had piggybacked

• past perfect

  past perfect

  Used to express a completed action that took place before another specific past action occurred.

  of piggyback.
  piggyback

  adverb

  on the back or shoulders.

Related Words

• add to
• amplify
• boost
• build up
• develop
• enhance
• enlarge
• expand
• heighten
• inflate
• intensify
• multiply
• reinforce
• strengthen