Related Clues:
- 'Not easily borne, very wearing (6)'
- For strength you want to make a fort for it, by the sound of it
- It was an effort for the ten of us to get so sour
- Rolling while grounded
- Challenging private transport is no good
- Needing forceful exertion
- Vigorous work on sutures
- Hard nut so sure to be in trouble
- Requiring great exertion
- Making great demands
- Physically or mentally demanding
- Testing the powers of endurance
- Burdensome Tory leader withdrawing
- Demanding levy in force
- Not sure flabby American is energetic