Complex sentence: Jack Donaghy (Alec Baldwin) married his girlfriend Avery Jessup (Elizabeth Banks) over New Year's, however, when he returns to New York following the nuptials he discovers that he is instead married to his employee and friend Liz Lemon (Tina Fey).
Split into simpler sentences: Jack Donaghy (Alec Baldwin) married his girlfriend Avery Jessup (Elizabeth Banks) over New Year's. However, when he returns to New York following the nuptials he discovers that he is instead married to his employee and friend Liz Lemon (Tina Fey).