What in this phrase suggests full-ness. The spoon definitely has some sugar, but how do we know it's full?
Uma colher com acucar (sorry about no accents, my keyboard is cheap) directly translates to a spoonFULL of sugar
It sounds weird when literally translated (as "a spoon with sugar"). But why translate it to English the way it does here? My guess is because it makes more sense in English the way it translates here.
Helps the medicine go down?
"Uma colher com açúcar" sounds a bit strange in Portuguese though, we usually say "uma colher de açúcar" in recipes and such.