I am trying to Solve this with LinQ C# : The Question is as follow: 

You're given a collection of sentences.
Return a collection containing the first word of each sentence, each word is separated by a single space character.

     public static IEnumerable<string> GetFirstWords(IEnumerable<string> sentences)
        {
                return sentences.Split(" ").Select(i => i.ToString()).Take(4);
        }
This is what i have written so far, I am getting an empty output. 