list all female (sex is F) candidate names in the alphabetical order.
SELECT t1.name FROM people AS t1 JOIN candidate AS t2 ON t1.people_id  =  t2.people_id WHERE t1.sex  =  'F' ORDER BY t1.name
list all refers to SELECT; female refers to sex = 'F'; candidate names in alphabetical order refers to ORDER BY name ASC; joining two tables refers to JOIN on a common column.