public void DeleteWordsByLength(int length)
{
var _words = sentences.SelectMany(x => x.Words).
Where(x => x.Length == length && x[0].IsVowel == false).Distinct();
for (int i = 0; i < sentences.Count; i++)
{
ISentence sentence = sentences[i];
for (int j = 0; j < _words.Count(); j++)
{
while (_words.Count() != 0 && sentence.Contains(_words.ToArray()[j]))
{
int spaceIndex = sentence.ToList().IndexOf(_words.ToArray()[j]) - 1;
sentence.Remove(_words.ToArray()[j]);
sentence.RemoveAtIndex(spaceIndex);
}
}
}
}