Complex sentence: The Yiddish language is written with the 22-letter Hebrew alphabet extended with several digraphs and letters modified with diacritical marks that are not currently used for writing the Hebrew language.
Split into simpler sentences: The Yiddish language is written with the 22-letter Hebrew alphabet. Several of those letters are combined as digraphs and others are modified with diacritical marks that are not currently used for writing the Hebrew language.