Find the names of procedures which physician John Wen was trained in.
SELECT T3.name FROM physician AS T1 JOIN trained_in AS T2 ON T1.employeeid  =  T2.physician JOIN procedures AS T3 ON T3.code  =  T2.treatment WHERE T1.name  =  "John Wen"
names of procedures = SELECT name FROM procedures; physician John Wen was trained in = JOIN between physician, trained_in, and procedures tables with filtering WHERE physician.name = 'John Wen';