- A. "the fever got the best of me": This means the fever overpowered or took advantage of the person. Therefore, it matches with IV. take advantage of something.
- B. "halcyon days": This refers to a period of peace and happiness in the past. Therefore, it matches with I. Peaceful time.
- C. "Achilles heel": This refers to a weakness or vulnerable point. In the context of gambling leading to being penniless, it indicates a weak spot. So, it matches with II. Vulnerable/Weak spot.
- D. "worth his salt": This phrase means competent or deserving of respect for one's work or profession. So, it matches with III. Competent for a work.
Therefore, the correct matching is:
- A - IV
- B - I
- C - II
- D - III