Put on a scale, set the reading to zero and add cold water just to cover, taking note of the weight of the water. Keep the bowl at room temperature, and out of direct sunlight, stirring the contents every day to refresh the surface and avoid mould. Add a tablespoon of unrefined sugar, honey or maple syrup for every 250g water, stir to dissolve, then cover with a cloth  this will not only protect the fruit from flies, but it will also allow the free flow of oxygen in the bowl or jar. But that is not the rule but the exception. Continue fermenting in the bowl, still covered with a cloth, for another two to four weeks, until it tastes beautifully acidic.
All fruits have more than a few grams of sugar.
( z0 have :ARG0 ( z1 fruit :mod ( z2 all ) ) :ARG1 ( z3 sugar :quant ( z4 more-than :op ( z5 few :op ( z6 mass-quantity :quant 1 :unit ( z7 gram ) ) ) ) ) )
(z0 / have-03
    :ARG0 (z1 / fruit
              :mod (z2 / all))
    :ARG1 (z3 / sugar
              :quant (z4 / more-than
                         :op1 (z5 / few
                                  :op1 (z6 / mass-quantity
                                           :quant 1
                                           :unit (z7 / gram))))))
All fruits have more than a few grams of sugar .
z1 :mod z2
z0 :ARG0 z1
z4 :op1 z5
z6 :quant 0
z5 :op1 z6
z6 :unit z7
z3 :quant z4
z0 :ARG1 z3