This　paper　proposes　a　new　kind　of　pushdown　transducer　ExPDT　to　do　XML　data　stream　evaluation　effectively　and　efficiently　for　XPath　queries　with　parallel　predicates,　multilevel　nested　predicates　and　predicates　with　value.　Compared　with　relative　researches,　ExPDT　expands　the　support　of　XPath　queries,　and　the　experiment　shows　that　it　improves　the　performance　of　XML　data　stream　evaluation.