How do I handel events like speech or key press in C# Servic

Question

I am trying to make a program basically a voice support so that recognizes speech and does the corresponding work I want this program to work even after the pc is in sleep state thats why i want service but after installing service successfully it does not hear any voice.

public partial class Service1 : ServiceBase
    {
        SpeechSynthesizer s = new SpeechSynthesizer();
        SpeechRecognitionEngine rec = new SpeechRecognitionEngine();
        Choices list = new Choices();

        public Service1()
        {
            s.SelectVoiceByHints(VoiceGender.Male)
            s.Speak("heyy");
            list.Add(new String[] { "hello", "how are you" });
            Grammar gr = new Grammar(new GrammarBuilder(list));
            try
            {
                rec.RequestRecognizerUpdate();
                rec.LoadGrammar(gr);
                rec.SpeechRecognized += rec_speachrecocnized;
                rec.SetInputToDefaultAudioDevice();
                rec.RecognizeAsync(RecognizeMode.Multiple);


            }
            catch { return; };

            InitializeComponent();
        }

        public void speak(String h)
        {

            s.Speak(h);
        }

        private void rec_speachrecocnized(object sender, SpeechRecognizedEventArgs e)
        {
                String r = e.Result.Text;
                if (r == "hello")
                {

                    speak("hello");
                }

                if (r == "how are you")
                {

                    speak("fine");
                }
        }


        protected override void OnStart(string[] args)
        {

        }

        protected override void OnStop()
        {
        }
    }