firmly|<~ ca fierul>(as) hard as iron/horn|<~ ca piatra>(as) hard as stone|<~ ca piatra>stone-hard|<~ ca piatra>stony|<~ ca piatra>flinty|<~ ca stejarul>(as) strong as a lion|<~ de cap>slow/dull of apprehension|<~ de cap>slow in the uptake|<~ de cap>beef-witted|<~