public static void InsertSentence(Sentences sentence)
 {
     using (var dbContext = new SentencesContainer())
     {
         dbContext.Entry(sentence).State = EntityState.Added;
         dbContext.SaveChanges();
     }
 }
        public static void DeleteSentences()
        {
            using (var dbContext = new SentencesContainer())
            {
                var sentencesToDelete = GetSentences();

                foreach (var sentenceToDelete in sentencesToDelete)
                {
                    dbContext.SentencesSet.Attach(sentenceToDelete);
                    dbContext.Entry(sentenceToDelete).State = EntityState.Deleted;
                    dbContext.SaveChanges();
                }

                //dbContext.Entry(sentencesToDelete).State = EntityState.Deleted;
                //dbContext.SaveChanges();
                //dbContext.SentencesSet.RemoveRange(sentencesToDelete);
                //dbContext.SaveChanges();
            }
        }