Find the year and semester when offers the largest number of courses.
return semesters ;return courses that  #1 offer ;return number of  #2 for each #1 ;return #1 where #3 is  the  largest ;return years ;return courses offer in #5 ;return number of  #6 for each #5 ;return #5 where #7 is  the  largest ;return #8 ,  #4
['select', 'project', 'group', 'comparative', 'select', 'project', 'group', 'comparative', 'union']