What are the names of the students who took classes in 2009 or 2010?
SELECT DISTINCT T1.name FROM student AS T1 JOIN takes AS T2 ON T1.id  =  T2.id WHERE YEAR  =  2009 OR YEAR  =  2010
students who took classes in 2009 or 2010 refers to filtering records where YEAR = 2009 OR YEAR = 2010; names of the students refers to SELECT DISTINCT T1.name; joining student and takes tables refers to JOIN...ON T1.id = T2.id;