text: public override int Next(int n){currentSentence += n;if (n < 0){if (text.Index == text.EndIndex){++currentSentence;}if (currentSentence < 0){currentSentence = 0;text.SetIndex(text.BeginIndex);return Done;}else{text.SetIndex(sentenceStarts[currentSentence]);}}else if (n > 0){if (currentSentence >= sentenceStarts.Length){currentSentence = sentenceStarts.Length - 1;text.SetIndex(text.EndIndex);return Done;}else{text.SetIndex(sentenceStarts[currentSentence]);}}return Current;}