Gulches Degree of Difficulty

There were _____ candles on your birthday cake. You put _____ more candle(s) on your cake. How many candles are on your cake now? ... We have _____ balls on the playground. _____ went over the fence. How many balls do we have left? ... Some are swimming and some are sliding on their bellies down a hill. How many penguins are swimming and how ... ................
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