had been impairing

• past perfect progressive

  past perfect progressive

  Used to describe an action that was ongoing continuously in the past up until another past event interrupted it.

  of impair.
  impair

  verb (used with object)

  to make or cause to become worse; diminish in ability, value, excellence, etc.; weaken or damage.

Related Words

• blunt
• damage
• debilitate
• decrease
• destroy
• diminish
• hurt
• lessen
• mar
• prejudice
• reduce
• spoil
• tarnish
• undermine
• weaken
• worsen