Database: scholar
Question: keyphrases used by dan klein in his emnlp papers
SQL: select distinct t2.keyphraseid from paper as t3 join paperkeyphrase as t2 on t3.paperid  =  t2.paperid join venue as t4 on t4.venueid  =  t3.venueid join writes as t5 on t5.paperid  =  t3.paperid join author as t1 on t5.authorid  =  t1.authorid where t1.authorname  =  "dan klein" and t4.venuename  =  "emnlp";