The invention relates to an agrochemical composition comprising propylene carbonate, up to 10 wt% of water, and compounds (I), their salts, tautomers, or enantiomers； wherein the variables are as defined in the description. The invention also relates to a process for the preparation of the composition, comprising mixing the propylene carbonate, compounds (I), and optionally an acid and/or cyclohexanone. It also relates to a method for controlling pests, which method comprises the application of the composition, or a dilution thereof, to plants, plant propagation material, or the locus of growth of the plants； the pests or their food supply, habitat or breeding grounds. Other objects are the use of cyclohexanone and/or an acid, in particular acetic acid, for stabilizing compositions comprising compounds (I)； composition for stabilizing water-soluble pesticides as defined in any of claims 1 to 9, comprising 1 to 50 wt% of propylene carbonate, 0.1 to 30 wt% cyclohexanone, and an acid； and an aqueous tank-mix composition comprising the composition in a concentration of 0.01 wt% to 10 wt% with regard to the total weight of the tank-mix.
