1. He has a weak character./He has no character. 2. He is
quite a character. 3. They are too sensitive (oversensitive).
4. They are revengeful/vindictive. 5. They have/get/take
(their) revenge. 6. Revenge/Vengeance. 7. Iwould try not
to stir an eyelid(turn a hair). 8. One must take precautions.
9. One must walk cautiously. 10. One may be injured. 11. One
may be/get injured. 12. Slippers. 13. People with no sense o f
humour. 14. This is characteristic of him. 15. A sink/a
kitchen sink. 16. A sensible person/A person of sense.