In a small saucepan, combine the vinegar, sugar and lemon juice. Bring the syrup to a boil over a low flame and reduce the liquid to about 1/4 cup. Set the syrup aside to let it cool completely. Place the cut strawberries in a bowl, if they are not very sweet add a scant tablespoon of sugar. Drizzle the balsamic glaze over the berries, toss gently and let stand for about 15-20 minutes, stirring occasionally.