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2.05 Verbs

(a) Compound verbs may be either hyphenated or written solid. The only safe rule is to check your dictionary:

  • freeze-dry
  • mass-produce
  • age-harden
  • spoon-feed
  • bad-mouth
  • extra-bill


  • waterproof
  • downgrade
  • sidetrack
  • proofread

(b) If the infinitive form of the verb (e.g. to air-condition) is hyphenated, retain the hyphen in all other forms, except as illustrated in (c):

  • The theatre was air-conditioned.
  • You need an air-conditioning expert.

(c) Hyphenate gerunds formed from hyphenated compound verbs only if they are followed by a noun object:

  • Dry cleaning is the simplest way to clean a sweater.
    Dry-cleaning the sweater should remove the stain.
  • Air conditioning is sometimes needed in summer.
    Consider the cost in deciding whether air-conditioning the building is feasible.